You may notice that a payment was marked as acknowledged in Altru but when you go on the payments record to unmark it as acknowledged the only option under task is to mark the payments as acknowledged even though Altru has already said it was acknowledged.
We are currently evaluating this issue and will update this article when we have more information.
Steps to Duplicate
Click Constituent > Constituent search
Search for and select a constituent
Click on the communications tab and notice they have a payment that was acknowledged
Click on the link that says acknowledgement
Click on the payment details tab
Click on the date of the payment
Notice under task it says mark acknowledged as if it wasn't already acknowledged in Altru