Connectivity Problems on Cell/WiFi and SIM Errors on Moto E4

Symptoms

• Republic Wireless app asks you to "buy a SIM card"
• Phone may show error "SIM card not ready" 
• Phone may show error "Authentication Error. Could not authenticate this device. Please make sure you have an active data connection. If this persists, please reboot your device."
• The cellular indicator or icon is missing
• Unable to call or message
• No service/data coverage on WiFi or Cellular networks

Environment

• Moto E4
• Build numbers before NPQ26.69-41-4-1

Resolution

• Update your Phone's Software to the latest build
  • Note:
    • If your phone is unable to update to the latest build, see Unable to Download the Latest Software Version on the Moto E4
    • If your phone shows a build number that is not NPQ26.69-41-4-1 or higher, it may still show as up to date. If this is the case, see Unable to Download the Latest Software Version on the Moto E4

Cause

There was an issue with an early version of the software before build NPQ26.69-41-4-1 which caused an issue with the modem on the phone. Updating your phone to the latest build will resolve the issue.

Additional Notes

In situations where your phone is behind several software versions, you will need to complete the process to update the system software multiple times

For information on how to check your Build number, see How to Locate the Phone's Build Number