Allow for proper closing of the db in case atomic throws an exception

[dpapathanasiou]

Hi @rajarshi and thank you for catching this!

Could you add a corresponding unit test? (i.e., just try using the same id twice, along the lines of how you discovered it)

I'll be happy to approve this, and merge it to main.

[rajarshi]

Thanks @dpapathanasiou - I've added a test case