S21 Ultra false overheating/moisture message

[Sephiroth1867]

Hi, my S21 Ultra has recently decided to tell me it's overheating or has moisture in the port every time I try and charge it. Seems to alternate between the two errors as and when it feels like it. I've had the charger port changed and I'm still getting the same message. I can't charge my phone at all as it comes up the second I plug in a charger. The phone definitely isn't overheating as the battery is dead and now I can't get it to charge to turn it on. I can't afford to buy a new Please tell me there's a fix for this that I can either do myself or won't cost 100's.

Thanks 

[JAMES4578]

Hi @Sephiroth1867  Best not to  let the Battery run down too much, can  discharge pretty  rrapidly once it reaches 10%. Do you have another charger you can try just to rule that out.   when Battery totally dead takes a bit of time but should eventually power up.  Alternatively try connecting to a computer to see if any joy there and see if you can enter Recovery mode.

Press and hold the Volume Up key and then press and hold the Power key
When the Android logo displays, release all three keys.
 Wait until the Android system recovery menu options appear, options to Reboot,wipe cache partition and Factory Reset for instance.

However if remains unresolved the Device would need to be inspected.