Too many characters in character literal

Too many characters in character literal

Process completed with exit code 1.

Non-nullable property 'Id' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Username' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Discriminator' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'AvatarUrl' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Username' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Password' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Message' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Converting null literal or possible null value to non-nullable type.

This async method lacks 'await' operators and will run synchronously. Consider using the 'await' operator to await non-blocking API calls, or 'await Task.Run(...)' to do CPU-bound work on a background thread.