Directorate of Income Tax (Systems) [DIT(Systems)]: Tackles technical issues related to the tax system, such as Assessment-related technical problems, National website issues, PAN-related technical glitches, Refund banker (SBI) issues, OLTAS (Online Tax Application System) technical difficulties, Non-filing of return notices and other system errors National Securities Depository Limited (NSDL): NSDL handles all PAN-related concerns, including Aadhaar linking, duplicate PAN allocations, digitization errors, discrepancy letters, online application issues, delivery problems, rejections, and upload delays. Unique Identification Authority of India Infrastructure Technology Services Limited (UTIITSL): This department, along with NSDL, handles PAN-related concerns like Aadhaar linking, duplicate allocations, digitization errors, discrepancy letters, online application issues, delivery problems, and rejections. E-Filing: Encountering problems while filing your return electronically? The e-Filing department tackles communication gaps, compliance portal queries, late filing requests, cybercrime concerns, DSC-related issues, FO Portal grievances, form submission problems, general inquiries, instant PAN issues, JSON utility glitches, outstanding demands, password resets, profile updates, rectification requests, refund inquiries, representative registrations, general registrations, TAN-related questions, e-proceedings, and verification problems. Grievance Redressal Mechanism under ITD-Contd..