My I phone 6s shows no service and cellular error

See these Apple articles below:

If you see No Service, Searching, or SOS on your iPhone or iPad

If you see No Service, Searching, or SOS on your iPhone or iPad - Apple Support

Manually update your carrier settings on your iPhone or iPad

Manually update your carrier settings on your iPhone or iPad - Apple Support

Update your network provider settings manually on your iPhone or iPad

Update your network provider settings manually on your iPhone or iPad – Apple Support (UK)

I got an issue my website is not responsive on my iPhone 8plus the web page is just loading like a basic one but I made it very responsive.

here is the link to my website please tell there is a mobile error or a responsiveness issue.

[Link Edited by Moderator]