Urgent help pls - amendment of service tax registration

Dear Experts Kindly advise me on the below queries in relates to service tax 01. Company having service tax registration Certificate with mutliple serivces, now two additional service are need to be inserted in the Certificate. while we are aheading for its amendment through ACES. we could not find any option to modify the RC. So kindly guide with the complete process " How the amendment will be carried on - either through manual application or online-application" 02. How the intimation will be made to Service tax department in regards to change of authorised personnel. Is this through manual application or electronic application. kindly advise the complete process Many thanks Aditya