Scheduled reports inactivated unexpectedly

Hello all,

We have an on premise instance in which we are receiving this email from a scheduled report:

Il report pianificato "Selir: Estrazione Ritiro POS (ID: aad37264-a8d8-11eb-9fec-0295aa324bdc)" è stato disattivato inaspettatamente. Per ulteriori informazioni, contattare l'amministratore.

It's basically saying that a specific report schedule was inactivated unexpectedly.

We reactivated the scheduled report 3 times, every time restart working as expected for a couple of days, then after it inactivates unexpectedly again.

Do you know a possible reason to it?

Thanks