tran_no in ReSA start after POS last used tran_no for Store/Register/Day - lands in SA_MISSING_TRAN

I have a client that is having an issue where it is creating TRAN_NO in ReSA that is higher than the last TRAN_NO used from the store/register for that day.

If the store had actually transactions of 6601-6650 during a given day, in ReSA, SA_MISSING_TRAN table, it will start with TRAN_NOs at 6651-6700.   Those transaction numbers are then processed through the store the next day, or sometimes the next couple of days.  Out of 450 stores, this is only happening to one store/register combination.  One last comment, it happens intermittently, meaning it will happen certain days, such as the 6th, 8th, and 10th, but not the 7th or 9th, and will stop doing this for a week, two weeks, or more, then pop back up.