So you are saying that the notice has been received on the old PAN number which has been cancelled?
So first get your PAN number changed with the company and since it's a penalty notice you need to go to your assessing officer who has issued this notice with the form 16 of your company your ITR, copy of your PAN Card, PAN cancellation application if available and explain the AO that you have filed your ITR properly and explain him the entire scenario and ask him to drop the penalty proceedings.
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