Cellular error and unable to active my phone

Please look at this --> If you can't activate your iPhone - Apple Support

ajmal154 Said:

"Cellular error and unable to active my phone: i can’t activate my iPhone 7"

Thank you for the screenshot.

Troubleshooting "No Service":

A. "No Service":

"No Service" is shown on the top-left corner of your screen. So, go here to fix that: If you See No Service or Searching on your iPhone or iPad - Apple Support

B. Contact your Carrier:

Having issues with Cellular, contact your Carrier, asking them to configure this to the correct settings. They configure all of this in the SIM card.