Website Hompage issue in Mobile version

my website is https://www.pcmicorp.com

I have installed Jetpack for the mobile version which automatically detects my website on the mobile os.

The issue is whenever I browse my website through a tablet or mobile it shows me my latest POST as a home page of the website and there is no way I can get my homepage to be shown. I am using a customized static theme. Please help me out with this. I have seen the funtional.php thing in previous forums but didn’t actually get what I have to do. I am new to php and codings. But I am pretty much tech savvy just let me know what should I have to do in order to get this thing work.