The Transmitter ID field will be grayed out on your pump if you have an active CGM session. You will need to select STOP SENSOR on your pump before you can edit the Transmitter ID.
Note: If you are using the Dexcom mobile app and the Tandem pump, we recommend pairing your Transmitter to your pump first, then pairing it to the Dexcom mobile app. Once the Transmitter is paired to both devices, you will be able to start a CGM session on either device.
