MS Exchange tasks gone

I have reminders synced with MS Exchange (Office 365). Now I have deleted a task list accidentaly and it's gone for good. It is not in MS Exchange recycle bin (deleted items) nor anywhere on my Mac. Please help me get it back.

Hi @kuba1231, thanks for using GoodTask. You can't restore removed data in GoodTask. To restore anything, you may need to restore from snapshot that's taken elsewhere such as iPhone's backup or iCloud backup. Thanks!

But if I'm using Exchange shouldn't this data be stored elswhere (trashbin in MS Exchange account)? Because I cannot find it anywhere in deleted data folder.

I'm not sure how Exchange manages the data. If they keep backups, it should be there.