Problems importing .OXF files - A ?27.00 transaction is lost, so balance is shown ?27.00 higher in GnuCash than the true balance.

[Alton Brantley]

I have noticed that sometimes the matching, particularly in recurring charges, will match a new transaction to a previously reconciled transaction of the same amount to the same vendor.
I would suggest checking whether there is a previous 27.00 transaction. Additionally, if you can identify the dropped transaction (check the date and amount) and then enter that one transaction by hand, and then re-reconcile for the same closing date, you should get your balance back.

I discovered this with the OFX imports, so after I import, I sort the transactions in DATE order to make sure all new transactions fall within the range of dates I expect.

Also, at least for me, it seems that many banks print the transaction with the DTUSER (date of transaction) on their printed statement, but put only the DTPOSTED (date the bank posted the transaction) in the OFX file.