Document cant be retrieved from File repository server

Hi Team,

BO XI 4.1 SP 6

We are facing a strange issue,

We have production environment in which daily recurring webi schedules run without any issues.

Now once we promote any report ( Issue is not with all reports ) but for some it is ( and the reports are not fixed)

from a Lower environment to production , the Schedule tends to fail intermittently with error "Document cant be retrieved from file repository server".

Although If I refresh the report it runs fine , a new schedule also is fine

This is very sporadic and not finding any pointers as to what might be causing it.

Requesting Inputs.