ADT-3 not filed by previous Auditor

A company is facing issues reappointing their new auditor for a five-year term because the previous auditor failed to file the necessary ADT-3 form. Despite receiving a No Objection Certificate and resignation letter, the previous auditor is unreachable and their office is closed. The new auditor has been appointed for the current financial year and the AOC-4 filed, but the five-year reappointment is blocked by the outstanding ADT-3. The discussion suggests exploring options with the ICAI if the previous auditor's membership number is known.