Error after verification in ITR 4

Users are experiencing errors when trying to verify ITR 4, specifically related to advance tax challan numbers and schema validation. Common issues include incorrect formatting of challan numbers, with the system sometimes auto-filling them without leading zeros or accepting non-numeric characters. Despite trying various solutions like refilling challans, updating software, and following IT department advice, the errors persist for some. However, a breakthrough was found by deleting pre-filled advance tax details and re-entering them manually, ensuring correct challan number formats, which led to successful filing for some users.