Populate joined table on create

I have 2 models in many to many relationship, so it has joined table. Users and Events, event_participants(joined table). So when im creating event i wanna populate this joined table with event id and ids of all users that i pass in request. For some reason it is trying to create users instead of just adding their ids. How to fix this? So on create need to populate joined table?

events.belongsTo(models.users, {
      foreignKey: {
        name: 'creatorId',
        allowNull: false
      },
      onDelete: 'CASCADE',
      as: 'creator'
    });
    events.belongsToMany(models.users, {
      through: 'event_participants',
      as: 'participants',
      foreignKey: 'eventId',
      otherKey: 'userId'
    });
    models.users.belongsToMany(events, {
      through: 'event_participants'
    });

  }

[kerimdragolj]

In case anyone needs, months later i found solution for this

function includeParticipants(hook) {
    if (hook.data.participants) {
        let participants = [hook.data.participants]; //convert data form request to array.
        participants.forEach((el) => {
            hook.result[0].setWorkers(el);
        });
    }
    return hook;
}

And i call this function in after hooks on create and patch like::

after: {
        all: [],
        find: [],
        get: [],
        create: [
            hook => includeWorkers(hook),
        ],
        update: [],
        patch: [
            hook => includeWorkers(hook),
        ],
        remove: []
    },

All of this happens in hooks of Event service. So when i create event, i get its participants and save it to joined table. Wish i knew this earlier. And stuff like this is NOT IN THE DOCS.

[foadyousefi]

Thanks @kerimdragolj Your solution worked for me also. But for anyone else reading this issue in the future, don’t forget to pass raw: false to context.params.sequelize. Because if raw: true, sequelize not adding the extra methods to associations.