Lockbox applying receipts as unidentified

[Givenchip]

My Autolockbox is set to apply payments to invoices using AutoAssociate. I removed MICR (routing and account) from transmission fields because customer account relationships are not set up.

Now issue is when a receipt made up of numerous invoices contains one invalid invoice #, lockbox is applying the whole receipt as "Unidentified" even though the rest of the invoices are valid.

I do have "Post partial amounts as undentified" selected when i submit Lockbox. "Reject entire receipt" is not selected.

Can anyone give me advice on what i need to do