How To Cure Scar On Lips?

Am Mr. Austin.I have a sore on my lip which many doctors told me is oral candiasis.it happened when i fell sick,i toke some self medication drugs and it reacted and brougth sore on my lip.after the sore healed there is this scar on my lip and since then it keep on growing bigger and bigger.some doctor gave me drugs to cure it but it sems not to be working.please i need help,i dont know wat else to do.