Failed to delete job & from the job scheduler timetable

What causes this issue?

The job named in the message was scheduled to start at a specific time
and date. The background processing system was unable to delete these
start specifications from its "time table" (table TBTCS).

System Response

If the FORCEDMODE parameter was set in the call to the BP_JOB_DELETE
function module, then the background processing system ignores this
error and deletes all other components of the job.
Otherwise, the deletion is terminated. The job has not been deleted.

How to fix this error?

You can delete the job again using "forced mode" to ignore the error.
This option is available in the programming interface in the
BP_JOB_DELETE function module and interactively in report RSBTCDEL.

Error message extract from SAP system. Copyright SAP SE.