Gave my sister my old iPhone 4S and she locked it forgot the password. Anyway I reset the fone and now in the activation process it's telling me to sign in with the Apple ID that was used to set up this iPhone.I put in the Apple ID but it won't work?

Gave my sister my old iPhone 4S and she locked it forgot the password. Anyway I reset the fone and now in the activation process it's telling me to sign in with the Apple ID that was used to set up this iPhone.I put in the Apple ID i used to set up the fone but it won't accept that Apple ID.. Am I doing something wrong or is there any way that I can check to make sure the Apple ID that I entered is correct? I think that i cleared my Apple ID of the fone when I transfered to my iPhone 5s and i set her up a whole new Apple ID and icloud.. Any help or suggestions would be appreciated!! Thanks :)