Two mortgage banks will forfeit more than $100,000 of interest on loans to a Manhattan couple, a judge ruled Wednesday, as a sanction for not acting in good faith in responding to requests for a mortgage modification.

Manhattan Supreme Court Justice Peter Moulton said Bonnie and Lawrence Singer were “thwarted by unresponsive loan servicers, unprepared lawyers, boilerplate form letters, and the banks’ or servicers’ often-changing and repetitive demands for financial information,” in their four-year quest to “climb out of default.”