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An item with the same key has already been added. Exception (Crash)

See original GitHub issue

I get this exception that crashes my app randomly. I am on 2.2.1 using the Xamarin.Forms version for the iOS version of my app.

Thanks

Unhandled Exception:
System.ArgumentException: An item with the same key has already been added.
  at System.ThrowHelper.ThrowArgumentException (System.ExceptionResource resource) [0x00000] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/throwhelper.cs:72 
  at System.Collections.Generic.Dictionary`2[TKey,TValue].Insert (TKey key, TValue value, System.Boolean add) [0x0008e] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/collections/generic/dictionary.cs:336 
  at System.Collections.Generic.Dictionary`2[TKey,TValue].Add (TKey key, TValue value) [0x00000] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/collections/generic/dictionary.cs:192 
  at FFImageLoading.Work.WorkScheduler+<RunImageLoadingTaskAsync>d__50.MoveNext () [0x000c1] in <6c0d6d3d38e24fc29999cada83cc7af7>:0 
--- End of stack trace from previous location where exception was thrown ---
  at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:143 
  at FFImageLoading.Work.WorkScheduler+<RunImageLoadingTaskAsync>d__50.MoveNext () [0x004d7] in <6c0d6d3d38e24fc29999cada83cc7af7>:0 
--- End of stack trace from previous location where exception was thrown ---
  at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:143 
  at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x00047] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:187 
  at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x0002e] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:156 
  at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x0000b] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:128 
  at System.Runtime.CompilerServices.ConfiguredTaskAwaitable+ConfiguredTaskAwaiter.GetResult () [0x00000] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:447 
  at FFImageLoading.Work.WorkScheduler+<TakeFromPendingTasksAndRunAsync>d__49.MoveNext () [0x00213] in <6c0d6d3d38e24fc29999cada83cc7af7>:0 
--- End of stack trace from previous location where exception was thrown ---
  at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:143 
  at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x00047] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:187 
  at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x0002e] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:156 
  at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x0000b] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:128 
  at System.Runtime.CompilerServices.ConfiguredTaskAwaitable+ConfiguredTaskAwaiter.GetResult () [0x00000] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:447 
  at FFImageLoading.Work.WorkScheduler+<TakeFromPendingTasksAndRun>d__46.MoveNext () [0x00069] in <6c0d6d3d38e24fc29999cada83cc7af7>:0 
--- End of stack trace from previous location where exception was thrown ---
  at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:143 
  at System.Runtime.CompilerServices.AsyncMethodBuilderCore.<ThrowAsync>m__1 (System.Object state) [0x00000] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/AsyncMethodBuilder.cs:1034 
  at System.Threading.QueueUserWorkItemCallback.WaitCallback_Context (System.Object state) [0x0000e] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/threading/threadpool.cs:1304 
  at System.Threading.ExecutionContext.RunInternal (System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, System.Object state, System.Boolean preserveSyncCtx) [0x0008d] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/threading/executioncontext.cs:957 
  at System.Threading.ExecutionContext.Run (System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, System.Object state, System.Boolean preserveSyncCtx) [0x00000] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/threading/executioncontext.cs:904 
  at System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem () [0x0002a] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/threading/threadpool.cs:1281 
  at System.Threading.ThreadPoolWorkQueue.Dispatch () [0x00096] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/threading/threadpool.cs:854 
  at ObjCRuntime.Runtime.ThreadPoolDispatcher (System.Func`1[TResult] callback) [0x00006] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/src/ObjCRuntime/Runtime.cs:238 
  at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback () [0x0000c] in /Users/builder/data/lanes/3818/ad1cd42d/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/src/mono/mcs/class/referencesource/mscorlib/system/threading/threadpool.cs:1206