Multiple processes using same invoice number

Hi Epicor community:

We just migrate from Epicor 10.1 to 10.2 and now we are having problems running Billing and Account Adjustments and some other interfaces and processes at the same time. For some reason sometimes the processes use the same invoice number.
We also have the problem when multiple batches are posted at the same time in Epicor they clash and something fails. It seems like the system can no longer deal with multiple processes running simultaneously.

Not sure if anyone else has experienced this?
Any help would be highly appreciated.

Thank you.

Kind regards,
Ninive

I think the silence here is because this is an odd issue. Is it possible you have things pointed to the wrong system?