If you see Connection Error while trying to scan your CGM, it is likely due to a proximity issue between the sensor and your phone. This error has to do with the NFC connection between your and the CGM sensor. Not to worry, this does not have to do with cellular data or wifi.
Try scanning the sensor again by touching your phone to the CGM sensor where the NFC technology is located. For iPhones, this will be right where your selfie camera is located while for Androids it can vary but most often is around the backside and central to the device.
For additional troubleshooting steps or other activation and scanning-related issues, we recommend taking a look at these articles: