Nullability of reference types in type of parameter 'sender' of 'void MainViewModel.Employees_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)' doesn't match the target delegate 'NotifyCollectionChangedEventHandler' (possibly because of nullability attributes).

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

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

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

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

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

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

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

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

Nullability of type of parameter 'activationState' doesn't match overridden member (possibly because of nullability attributes).

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

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

Nullability of reference types in type of parameter 'sender' of 'void MainViewModel.Employees_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)' doesn't match the target delegate 'NotifyCollectionChangedEventHandler' (possibly because of nullability attributes).

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

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

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

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

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

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

Nullability of type of parameter 'activationState' doesn't match overridden member (possibly because of nullability attributes).

Nullability of reference types in type of parameter 'sender' of 'void MainViewModel.Employees_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)' doesn't match the target delegate 'NotifyCollectionChangedEventHandler' (possibly because of nullability attributes).

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

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

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

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

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

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

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

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

Nullability of type of parameter 'activationState' doesn't match overridden member (possibly because of nullability attributes).

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

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

Nullability of reference types in type of parameter 'sender' of 'void MainViewModel.Employees_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)' doesn't match the target delegate 'NotifyCollectionChangedEventHandler' (possibly because of nullability attributes).

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

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

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

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

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

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