Received wrong notice from CE commissioner

Hello friends,  

My company, a consultancy service provider, received a notice in Nov'14 from Central Excise Commissionerate that half yearly return(ST-3) for Oct'12 to Mar'13 has not been deposited.  

But I have alredy deposited it within time and have the bank receipt for it.

What should I do? Please also tell me the mail address on which I should reply.

Thanks in advance.