REP-1401: '': Fatal PL/SQL error occurred. REP-0069: Internal error REP-57054: In-process job terminated:Terminated with error: REP-1401: '': Fatal PL/SQL error occurred.

If the RDF Report is failing with Fatal PL/SQL Error.

Reasons could be either of the below three

1) Formula column is returning Null value
2)Data type variable is returning more than expected size of variable.
3) Data type of variable are mismatching.