I bought a new iphone 7 plus from cricket in the store on September 2019 and since i got it I noticed that the phone would restart every time the battery charged to97-100 percent and it would do that sometimes and now it does it more often what should I do did i get a faulty phone or was it not new ? They told me it was ..?
I would contact Apple support. The phone is still under warranty. A. Do you have the most recent and up to date software version? If not, download that. Apple phones can be pretty picky about things if they are not up to date. B. To help you save some time, I’d do a complete back up of your phone. This will store important stuff like cal logs, contacts, messages, pictures, emails, apps, and app settings into your iCloud account. Most likely you will be asked to wipe your phone and do a complete system restore to correct the issue when you call Apple Support