Read it carefully, note the deadline, collect records and respond on the portal with proper reasoning.
Do not ignore it
A notice is not an order. It is an opportunity to explain. Ignoring it is what usually converts a small query into a demand with interest and penalty.
Five steps
Check the section, period and deadline. Match the allegation to your returns. Collect invoices, e-way bills and reconciliations. Draft a reply that answers every point. File through the portal and keep the acknowledgement.
When to escalate
If the demand is high or the issue is a matter of interpretation, involve a professional before replying. A well-structured first reply often decides how the matter proceeds.
This article is general information, not legal or tax advice. Rules and due dates change: please consult a professional before acting.