How to define which user "runs" an automated process?

Hi Comunity,

We have a process that is triggered by a timer and calculates KPI's of projects during the night.

The process is "run" by a user as left the company and that is no longer active. This is probably what is causing the process to not tun completely because if I run it manually everything goes fine.

How do I define which user should creatio use to run this automated process?

Thanks,

Luis