PLS-00368: in RAISE statement, string must be an exception name

PLS-00368: in RAISE statement, string must be an exception name

Cause: The identifier in a RAISE statement is not a valid exception name.

Action: Make sure the identifier in the RAISE statement was declared as an exception and is correctly placed in the block structure. If you are using the name of a PL or SQL predefined exception, check its spelling.