CGM features and fixes · Medtrum TouchCare Nano CGM

Medtrum TouchCare Nano CGM sensor error

ERR asks for a new calibration after 15 minutes. ??? means no readings: keep the sensor on until a Sensor Failure alert appears, then change it. (Medtrum UK user guide, p. 16; Medtrum UK user guide, p. 14)

What the maker says to do

1. If the app shows ERR, enter a meter BG after 15 minutes.
2. If the app shows ???, do not remove the sensor until you get a Sensor Failure alert.
3. If the app shows NO READINGS, check if the sensor was bumped or came loose.
4. If you get Sensor Failure, change the sensor now.

The Nano CGM is not FDA-cleared and the EasySense and EasyFollow apps are not in the US App Store, so these answers come from Medtrum's international (WW) and UK English pages and guides.

More on the Medtrum TouchCare Nano CGM

• Follower app not updating
• Signal loss
• Warm-up
• Sensor failed early
• Alarms not sounding
• Follower not getting alerts
• Compatible phones

Sensor error on other CGMs

• Dexcom G6
• Dexcom G7
• Dexcom ONE+
• Dexcom Stelo
• FreeStyle Libre 2 and 2 Plus
• FreeStyle Libre 3 and 3 Plus
• Eversense 365
• Medtronic Simplera
• SIBIONICS GS1

Sources, quoted

• Medtrum UK user guide, p. 16: “SENSOR CALIBRATION ERROR Enter meter BG after 15 minutes.”
• Medtrum UK user guide, p. 14: “??? - No readings. Do not remove the Sensor until you get “Sensor Failure” Alert.”
• Medtrum UK user guide, p. 16: “NO READINGS”
• Medtrum UK user guide, p. 16: “Check if the sensor gets bumped or dislodged.”
• Medtrum UK user guide, p. 16: “SENSOR EXPIRED, SENSOR FAILURE”
• Medtrum UK user guide, p. 16: “Change Sensor now.”

Every quote is checked against its source page before each update of this site; last checked 2026-10-06. Makers change their apps; the source page is the authority when it differs.