Have you tried a different charger? Have you charged the device with multiple outlets? Does it allow you to reach a full charge when the device is placed into safe mode?
You can try these steps, your phone won't be wiped. Enter settings, then type reset into the bar. Do reset settings, accessibility, and network. Reboot afterwards.
Also, are you using a wireless charger without a fan? It produces more heat than wired.
this last Monday (4/29) I woke up and my Galaxy S10+ was extremely hot, right under the Bixby button and on the back in the same area. I haven't charged it overninght because it was charged the evening before. The one thing I noticed is my Watch Active died overnight (i thought it will last till the morning). I checked and there were no apps draining the battery, yet the phone was really hot. After I restarted the S10+ it cooled down and is still ok. At the time of restart I put my Watch Active on the charger (letting you know in case it matters, it was charging however it didn't power on). Today I noticed that the left side of the phone (that was hot) seems to be swollen a little compared to the right side that remained cool. Please see the attached photos. Hope it's not the Note 7 disaster all over again (this time without even charging). Anyway, this phone is not in its original state (pretty much the body is broken), please advise how to resolve the issue.
I can understand your concern, just send us a private message with your model code and IMEI number and we'll be happy to look into this for you.
My.samsung s10 plus was very hot today when I had my data on and I had to switch it off for about 45 minutes... i just got this phone last week and it's has always been hot when using mobile data.....All the sides and back are so hot that I had to drop it....please why is that happening .my previous s8 plus wasn't like this..