iphone need to cool down before you can use it

I got the message "iphone need to cool down before you can use it" I am using iphoneX. I can only use the phone for about 10minutes on replying messages or webpage browsing (non-video). The phone itself is not worm, room temperature is 70 degrees F. I tried closing all apps, and a restart the phone, but it is still doing the same thing. Does anyone has the same issue and know how to fix it? I sure don't want to wipe and reinstall everything. Thx for your help.