My phone is getting very hot from one side (left) ?S10plus

I am continuously facing a very weird problem.Everytime i call someone or recieve a call , the phone automatically switches from earpiece to speaker and more to that even if switch back to earphonr it happens again! Please help

I got note 9 less than a year ago .... It has started heating up on left side on normal usage and also charging is very slow !I am scared