I often get little gaps in the line like that.
Well, maybe every third sensor. A gap or three, less than half an hour each, usually in the first few days. In every case the sensor has settled down and been fine after that.
Never bothered to complain or contact Abbott, although I have done so for sensors which read very low, or are otherwise erratic. Although almost all my sensors read approx 1mmol/l lower than finger pricks. But i just allow for that.
Edited to add: I use the Libre reader, not a phone.