Seaquel
SQL Server error code

SQL Server error 3990

SQL Server raises error 3990 at severity 16, which marks a problem with the query or data that you can correct.

Transaction is not allowed to commit inside of a user defined routine, trigger or aggregate because the transaction is not started in that CLR level. Change application logic to enforce strict transaction nesting.
Msg3990
Severity16
Group3000–3999

Source: Database Engine events and errors