We also have this issue, and not just one.  We have 2 vendors who should have received a total of 14 online billpay checks in a 2week period.  None of those checks were received or cashed. Who knows what that problem could have been!  Now we have 14 different checks from a prior period (90 days ago) that were auto-voided by Bill.com.  That action DOES void the bills in QB also.  So now my bank recs from the last 3 months are all incorrect, with the beginning balance of the most recent reconciliation showing these 14 checks as the problem. 

So

1. the bills are now correctly in a payable status again, but

2. QB cash balances/bank recs for the original month plus 2 more months are incorrect

3. We also have the money coming back from the void to our bank account/QB bank feed in the current month that need some sort of entry/transaction to match to.

I am not concerned with re-paying the vendor, that is the easy part.  Do we fix #2 and #3 by journal entries??

Thanks.