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Using Dexcom ONE in the Long Run

What do I do if I receive the Sensor Failed alert?

Last Updated · November 3, 2022

If you are receiving a Sensor Failed Alert on your Dexcom ONE, and your inserted sensor will no longer give CGM values, remove the failed sensor using the in-app Sensor Removal Instructions.

Insert a new sensor and contact the Dexcom support team at

5-step learning journey

Discover education resources, organised in a 5-step journey, to learn key information about your Dexcom ONE CGM system, from getting started, your first 10 days, to using Dexcom ONE in the long run.

Step 1: The basics of CGM
Step 2: Getting started
Step 3: Your first 10 days
Step 4: Using Dexcom ONE in the long run
Step 5: Understand your Diabetes trends