Seaquel
SQL Server error code

SQL Server error 6386

SQL Server raises error 6386 at severity 16, which marks a problem with the query or data that you can correct.

Cannot convert a selective XML index to a secondary selective XML index using the DROP_EXISTING option. '%.*ls' is a selective XML index.
Msg6386
Severity16
Group6000–6999

Source: Database Engine events and errors