What does ? Mean in the right top corner of the Dexcom 7 plus?

Any help would be greatly appreciated! Thanks

It means that the receiver can’t understand the transmitter, sometimes out helps to enter 2 blood sugar readings from your glucometer. I have got this when I get a sudden high or when I try to stretch the time on my sensor to long

Means Dexcom is having trouble making sense of the readings it’s getting. Rather than give you a bogus number or a number that could be way off it goes to ???. If it doesn’t come back within 3 hours you may have a bad sensor and then would call customer service and they will replace the sensor if it’s less than 7 days old. I often will get ??? when my sensors are dying at 10 to 14 days. Otherwise I rarely experience them. I’ve heard they can occur when sugars are rapidly changing though.

It can sometimes happen when in the bath or swimming and the system will come back to working after the transmitter has had time to dry out. If it doesn't come back in 2-3 hrs, you should call Dexcom tech support and see if there is anything they suggest. Usually if it hasn't come back in a few hours, you'll end up needing to change the sensor. Call Dexcom first, because if it has been less than 7 days and they tell you to change the sensor, they'll replace it for free.