Hi I having service tax registration number XXXXXXXSD002. and I pay my service tax through online portal manage by NSDL, but by mistake I enter XXXXXXXSD001 (wrong service tax number) in the online portal it shows my name and my correct address, so I keep on depositing my service tax every month to this number suddenly I came to know this was wrong service tax number. sir I have seen my name that's why I keep on depositing the service tax through this number, I have pay service tax to inactive number from period 12/02/2015 to 25/03/2016 one year to the inactive service tax number .now the service tax department asking me to take the refund and pay 18% interest on that apart from that they are saying they cant refund more than 7 month service tax . I am complitely puzzeled dont know how they can do this i deposited all payments still they are sending me so many technical letrs. PLEASE help me what can i do now .