Cancellation of registration for migrated taxpayers requires identity, reason, declaration of non liability and authorised verification. Form GST REG-29 enables cancellation of registration for migrated taxpayers by collecting GSTIN, contact details, legal name, correspondence address, the reason for cancellation and whether any tax invoice was issued; it requires a declaration of non-liability and verification including Aadhaar, PAN and authorised signatory's signature, name, designation, place and date.