Mutation Of My Land By Using Forged Affidavit And My Forged Signature

I live in Patna. my land is in Aurangabad Bihar. and father made an affidavit on my name that my son wants his property to be transferred on my father name. and he gave an application for mutation in block by using my signature. my father has sold out his allotted property earlier. I need fast relief for this type of forgery.