19 September 2014
Amend form ST-1 and submit online, take a print of the same, have it signed from the assessee, and submit the ST-1, original copy of ST-2 issued earlier, and other documents (if any, as a proof of change i.e. address change etc.) to the department and get one copy ST-1 acknowledged by the department.
Once changes are done, take print of new form ST-2 and get it signed from the department.