RTA Hyderabad — vehicle ownership transfer issue

Address: Hyderabad, Telangana, 500050

Dear sir,
I have sold my yamaha rx 100 bike to someone. The registered number is ap31g5531 in year 2010 and the buyer assured that he will get the necessary ownership transfer done but still the buyer has not registered on his name even though i have asked him several times to get the transfer done. I kindly request to help solve this issue. I request the authority rta to take necessary action...