ASCII Database backup job is failing with error like 'ORA-31626: job does not exist'.
According to Doc ID 2197898, the error like 'ORA-31626: job does not exist', indicates that Data Pump job uses a invalid reference to a job which is no longer executing.
Starting to see Data Pump failures after it has been running fine for a long time may be due to the fact that the data dictionary of this database has an issue.
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Run catproc script to fix this issue:
2.To recompile invalid objects, if any:
Try to reproduce the issue.