When generating payments for direct debit processes, users may specify whether to include all outstanding pledge and recurring gift payments, or they can choose to only generate payments for a specific selection of revenue records. When a selection is specified and the generate direct debit file process is saved and then re-opened to be edited, the selection is removed from the process. This issue was resolved for versions 2.91 and higher, but still occurs in lower versions.
Download and install the latest patch, which contains all fixes from previous patches. If you are running an older version, download and install the latest version and then the patch.