MERGE statement ANSI cardinality violation on table '%1'

Error constant SQLE_MERGE_CARDINALITY_VIOLATION
ODBC 2 State ERROR
ODBC 3 State ERROR
Parameter 1 Name of the table being updated
Severity 16
SQLCODE –1211
SQLSTATE 23509
Sybase error code 13304
Probable cause

You have attempted to execute the MERGE statement and the same row is the target of a WHEN MATCHED clause more than once