If you have archived a payment but can no longer see it on the All payments grid, then you will need to filter on the date. Payments older than two months can now be found using this method.
If you would like to adjust the timings for automatically deleting archived batches, then you would need to change these on the Payment Profiles. An administrator would need to do this and there is a link to an article below detailing the steps.
https://help.pt-x.com/hc/en-us/articles/115001243491-How-do-I-archive-my-payment-files-