Database - LOCKED?

Hello! Im setuping the mAirlist for one customer in Croatia, and they have a lot problems with playlist. One of them is DB app blocking when generating PL for more than 3 hrs.
Also, they get error - Database LOCKED…
They have latest version of software, local DB and Windows 11.

Is there more than one mAirList computer/process involved?

No, only one. They use same PC for playout and DB playlist generation/ads…

I tried to create a playlist based on an hour template with an end of hour at 04:00:00 and it worked without problems.
Can you give me more informations, please?