A:AnswerDarrell, the new phone requires a new style SIM card. You will need to go to ATT and request a new SIM. There may be a small fee for the new card but will continue to be on the same plan without a required upgrade.
A:AnswerSounds like the battery is at end of life. You can take the phone to Apple and have the battery replaced for a fee. ( I had this done on an iPhone 7 for $50)