Cannot convert null literal to non-nullable reference type.

Nullability of reference types in type of parameter 'x' of 'bool LambdaEqualityComparer<T>.Equals(T x, T y)' doesn't match implicitly implemented member 'bool IEqualityComparer<T>.Equals(T? x, T? y)' (possibly because of nullability attributes).

Nullability of reference types in type of parameter 'y' of 'bool LambdaEqualityComparer<T>.Equals(T x, T y)' doesn't match implicitly implemented member 'bool IEqualityComparer<T>.Equals(T? x, T? y)' (possibly because of nullability attributes).

Nullability of reference types in type of parameter 'x' of 'bool LambdaEqualityComparer<T, K>.Equals(T x, T y)' doesn't match implicitly implemented member 'bool IEqualityComparer<T>.Equals(T? x, T? y)' (possibly because of nullability attributes).

Nullability of reference types in type of parameter 'y' of 'bool LambdaEqualityComparer<T, K>.Equals(T x, T y)' doesn't match implicitly implemented member 'bool IEqualityComparer<T>.Equals(T? x, T? y)' (possibly because of nullability attributes).

Nullability of reference types in type of parameter 'buffer' of 'long ObjectDataReader.GetBytes(int i, long fieldOffset, byte[] buffer, int bufferoffset, int length)' doesn't match implicitly implemented member 'long IDataRecord.GetBytes(int i, long fieldOffset, byte[]? buffer, int bufferoffset, int length)' (possibly because of nullability attributes).

Nullability of reference types in type of parameter 'buffer' of 'long ObjectDataReader.GetChars(int i, long fieldoffset, char[] buffer, int bufferoffset, int length)' doesn't match implicitly implemented member 'long IDataRecord.GetChars(int i, long fieldoffset, char[]? buffer, int bufferoffset, int length)' (possibly because of nullability attributes).

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

Cannot convert null literal to non-nullable reference type.