Seaquel
SQL Server error code

SQL Server error 5324

SQL Server raises error 5324 at severity 15, which marks a problem with the query or data that you can correct.

In a MERGE statement, a '%S_MSG' clause with a search condition cannot appear after a '%S_MSG' clause with no search condition.
Msg5324
Severity15
Group5000–5999

Source: Database Engine events and errors