Non-nullable property 'Token' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the property as nullable.

Non-nullable property 'UserId' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the property as nullable.

Non-nullable property 'LecturerId' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the property as nullable.

Dereference of a possibly null reference.

Non-nullable field '_connection' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the field as nullable.

Possible null reference return.

The target framework 'netcoreapp2.2' is out of support and will not receive security updates in the future. Please refer to https://aka.ms/dotnet-core-support for more information about the support policy.

The target framework 'netcoreapp2.2' is out of support and will not receive security updates in the future. Please refer to https://aka.ms/dotnet-core-support for more information about the support policy.

The target framework 'netcoreapp2.2' is out of support and will not receive security updates in the future. Please refer to https://aka.ms/dotnet-core-support for more information about the support policy.