Go to the apple shop. Maybe is an unlocked phone that was not properly unlocked.
Did you upgrade ios on your iPhone 7. If you see No Service or Searching on your iPhone or iPad (Wi-Fi + Cellular), or can't connect to a cellular network or cellular data, follow these steps: #Check your coverage area #Restart your iPhone or iPad #Check for a Carrier Settings update #Take out the SIM card and put it back in #Reset your Network Settings. #Contact your carrier
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