Seaquel
SQL Server error code

SQL Server error 6223

SQL Server raises error 6223 at severity 16, which marks a problem with the query or data that you can correct.

Type "%.*ls.%.*ls" is marked for native serialization, but field "%.*ls" of type "%.*ls.%.*ls" is of type "%.*ls.%.*ls", which is not marked with "LayoutKind.Sequential". Native serialization requires the type to be marked with "LayoutKind.Sequential".
Msg6223
Severity16
Group6000–6999

Source: Database Engine events and errors