Service
Iv no service all day on my I phone 7 but yet can use internet, WhatsApp etc
iPhone 7, iOS 13
Question marked as
If you have a Wi-Fi connection you can use the Internet. If your phone shows “No service” in the status bar see—>If you see No Service or Searching on your iPhone or iPad - Apple Support
As you have an iPhone 7 this also may be relevant—>iPhone 7 Repair Program for "No Service" Issues - Apple Support
Finally, consider the possibility that your carrier has a local outage. You can call them and ask, and also see this crowd-sourced site: Down Detector - outages