Liquid damage is a big cause of overheating. I'd recommend opening it up and cleaning out any debris or corrosion that's going on inside the phone. Aside from that, keep your phone in cool places and turn it off if it starts overheating.
We have a chance to guarantee our right to repair electronic
equipment—like smartphones, computers, and even farm equipment. This is a once-in-a-generation
chance to protect local repair jobs—the corner mom-and-pop repair shops that
keep getting squeezed out by manufacturers.
Join the cause and tell your state representative to support Right to Repair. Tell them you believe repair should be fair, affordable, and accessible. Stand up for your right to repair!