Error on using a custom class list

[Noslin22]

First, I want to say that I'm Brazilian, so sorry for my English.

Describe the bug
It's the first time I'm using this package and I really liked it when using common values, like strings and ints. But today I tried to do with a class, and it says that "type 'String' is not a subtype of type 'Map<String, dynamic>'" on the 39 line. But when I click on the item, it says that it's a class. I have the toJson function on my class.

To Reproduce
Steps to reproduce the behavior:

1. Create a UserModel class with name and password.
2. I did the same model of the example.
3. I'm running on Windows 10.
4. When I click on the field, it stops.

[Noslin22]

I saw the method toJson you use was different of mine, sorry for bothering. Closing.