Please help me to correct my sentences

Please accept this letter as notice of my resignation due to a serious health issues with which I have recently developed with post covid problems.

I would have stayed with the company but due to health problems, I have to leave this Job to rest and recuperate.

I am currently suffering from post covid issues after I had recovered from Coronvirus illness earlier this month. I have visited the hospital many times, but there is no significant improvement, and my doctor has advised me to undergo further medical tests which include MRI scan and other tests. Therefore, I have decided to do the further treatments in my hometown.

Due to this situation, I have decided to leave the company and go back to my hometown to have a better treatment there. It is, therefore, requested that I may kindly be relieved from my post at the earliest.