Usually I get those sensor updating messages for one of two reasons:
-the sensor is about to expire (each sensor session lasts about a week, I find that I get this error message towards the end of my week, and my BG readings can be a little off)
-I have entered too many BG from my meter. This is a hard adjustment from the Dexcom, which didn’t care how many times you calibrated it in a day and didn’t ever prompt you for a BG unless it actually needed it. However, there is a problem with the 670G software…if you enter a BG or calibrate too often, it will start rejecting your BG, but ask for more BG, or go into this sensor updating mode…so you can’t reliably follow the prompts you will get for more BG or calibration. It truly only wants to be calibrated twice in a 24 hour period, and if you exceed that, things start to devolve. This is where technical support was really helpful to me. If there is a discrepancy between your meter reading and the sensor (this is particularly common at the beginning of a new sensor session), then it will reject your calibration. The problem is, it will as for another BG…DON"T DO IT…you must wait at least an hour to re-enter another BG…and even longer to recalibrate. At Medtronic they can tell you exactly how much of a discrepancy will kick you into this vicious cycle (I had it written down but lost it). Bottom line is, you can’t follow the prompts uncritically. This was a source of a lot of frustration for me…but over time, I’ve figured out how to play by the underlying rules of the game.
Also, I typically only put on a new sensor first thing in the morning and I fast for the first two hours that it is in ‘warm up’ mode so that when I enter the first BG and calibration, I am not trending up/down. I find that if I do a calibration or enter a BG in a time of BG transition (ie after a meal, dawn phenomena, stress), there is more likely to be a large discrepancy between the sensor reading and the meter reading and that throws you into the vicious cycle described above.
My guess is that a few sessions with the folks at Medtronic on the phone will clear up a lot of the confusion.
The crimping happened for me when I used my abdomen, the fiber would dislodge and crimp…but as I mentioned before, that’s because of my body habitus post-twin pregnancy.