The process 'C:\hostedtoolcache\windows\advinst\21.9\x86\bin\x86\advancedinstaller.com' failed with exit code 3758162020

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

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

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

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

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.

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

Possible null reference argument for parameter 's' in 'int int.Parse(string s)'.