MC6020: {0}:TypeArguments='{1}' is not valid on the tag '{2}'. Either '{2}' is not a generic type or the number of Type arguments ...

MC6020: {0}:TypeArguments='{1}' is not valid on the tag '{2}'. Either '{2}' is not a generic type or the number of Type arguments in the attribute is wrong. Remove the {0}:TypeArguments attribute because it is allowed only on generic types, or fix its value to match the arity of the generic type '{2}'.