[BUG] Unfriendly error message when joining pool already joined: "'NoneType' object is not iterable".

Describe the bug When attempting to join a pool, I get the following exception.

$ chia plotnft join -i 2 -u https://asia1.pool.space -y
{'authentication_token_timeout': 5,
 'description': 'Welcome to Space Pool. By creating this Plot NFT, you agree '
                'to the following terms https://pool.space/terms',
 'fee': 0,
 'logo_url': 'https://pool.space/logo-250.png',
 'minimum_difficulty': 1,
 'name': 'Space Pool',
 'protocol_version': 1,
 'relative_lock_height': 64,
 'target_puzzle_hash': '0x2f2c9ba1b2315..........e7b14d942b969ed5d57'}

Will join pool: https://asia1.pool.space with Plot NFT 449168170.
Error performing operation on Plot NFT -f 449168170 wallet id: 2: 'NoneType' object is not iterable

To Reproduce

Steps to reproduce the behavior:

On the cli, chia plotnft join -i 2 -u https://asia1.pool.space -y

Expected behavior

Pool can be joined.

Desktop

OS: Linux OS Version/Flavor: Ubuntu 20.04.2 CPU: Intel i3-3220 Blockchain: 1.2.0

Additional context

Updated from 1.1.8dev0, and I keep the data in ~/.chia/

[Sosonedu]

delete the config order and reinstall chia…

[TheOv3rminD]

This happened to me when I tried to change pools while I was building plots for the associated pool NFT. I figured that what the problem was, so I let the plots finish and tried again and then it worked just fine.