S8 Active doesn't charge after Android 9.0 update.

I recently finished a repair on a Galaxy S8 Active and all was well. I decided to update it to the latest version of android when I finished. It successfully updated to android 9.0, but afterwards it would not charge on both wireless and wired charging. It recognizes the charger, says charging, but loses battery. I took the motherboard out and reconnected every flex cable and ensured they all had a good connection to rule out a hardware problem, but that had no effect. I charged the Active battery by plugging it into a normal S8 and it charged to 90%, so the battery is fine. l thought that flashing Oreo stock firmware would solve the problem, but I haven’t been able to find any in the right carrier. I’ve only found Sprint and T-Mobile but I need AT&T. Right now, I’m downloading some unlocked firmware in android 7.0 and i plan to update it to 8.0 (linked below). I don’t think the S8 Active is even sold unlocked. I’ve included pictures of the software information of the phone. Will this firmware work on the phone and will it solve the charging issue?

https://samsung-firmware.org/download/Ga...

I received a new daughterboard and sim tray. The phone recognized the sim and nothing was out of the ordinary. It connected to the network and could call and use LTE. replacing the daughterboard had no effect on the phone, and the same problem persists. I am now very close to certain that this is a purely software issue. I am leaving a sim card in the phone and I’m leaving the phone on for 7 days to remove KnoxGuard. After that I plan on attempting to flash Oreo firmware. I will give an update for anyone who is having the same issue in the future.