Running activities never finish

Hi

did anybody come accross the issue that a running activity is never stopping?

for example:

- a preparation step for few 100 bank master record is running for 92 days.

- preparing less than 10 new objects is running already for 5 hours.

- file validation of 1 purchasing info record is running for 3 hours.

I had this issue already in different systems, different releases. Currently it is a 2021.

Does anybody has a solution to this issue?

Thanks!

Best regards

Klaus