my i phone 5c has come back from repair and now i cant sing in to my aoole id having big problems

I appear to have forgotten the correct apple id and pass word to gain access to my phone. have tried making new apple id and passwords now im just confused and now the phone has been disabled and telling me to create a new password ,but now I cant verify my apple account as ive forgotten a security question. how do I get out of this with out being charged ? iPhone 5c