Battery not functioning properly

@johnconsta36192 that actually sounds like a battery issue. It most likely is unable to hold a full charge. Replace the battery and re-evaluate. Since iFixit does not yet have a specific guide for this, use something like this video to work on your phone. You do not have to remove the main board, but you will need to disconnect the flex cables from the battery to the main board.

Replacement batteries are readily available at many online stores.

While you work on your phone, take lots of pictures. Once you are done with it, take those pictures and create a guide for iFixit. That will help the next person that has a device with the same issues as you do. It's easy and fun to create these guides. https://ifixit.com/Guide/new The iFixit community will appreciate this.

Repair is War on Entropy!