BSNL Retailer's — Extra charges of Top-up vouchers

Retailers in Malerkotla charging the old service tax i.e. 12.30% from the customer even though they know that service tax charges has been reduced. In BSNL exchange counter they are charging the existing service tax i.e. 10.30%. When asked for bill they refused to give so. I request the administration to check this as early as possible.