Wrong entered assessee code in service tax challan

Dear Sir,

We have two companies in our group of company, say A Co.Pvt Ltd and another B Co Pvt Ltd.

Balance due in B Co Pvt Ltd and A Co.Pvt Ltd has nill balance.I have paid ST amount alongwith Interest & Penalties but when I make payment through online , by mistake I have written Assessee Code of A Co.Pvt Ltd.

Now please advice me how to correct the same.

I need your guidance on urgent basis.

With best regards

Jayanta