When importing Bill Payments, Transaction Pro Importer failed to find a matching Bill (for Bills Payments) in QuickBooks Desktop (QBDT) file even though the record does exist. Error message "Could Not Find Matching Bill to Apply Bill Payment" displays on the Transaction Log.
First, make sure the Bill is still in an Open status in QBDT as well as the remaining balance is equal or more than the payment amount being imported.
If the above has been verified, please be aware that there is a bug in the QuickBooks Software Development Kit (QBSDK) in relation to these type of transactions. If the Bill Reference Number exceeds the limits of an integer data type (2147483647), then Importer will be unable to import the transaction. Basically, QBDT will not return query results on any number that exceeds the limits of an integer (2147483647).
In addition, on Bill Payment imports when the Reference Number is a string (contains non-numeric numbers), the QBSDK will only find Bills that have 19 or less characters in the Bill Reference Number.
Two options exist:
Shorten the Bill Reference Number
Precede the Bill Reference Number with a letter so that QB will treat the data as text (making sure the Bill Reference Number is not longer than 19 characters)