Hi Pipp,
Yes I have contacted Abbott about this, but I find a 100% failure rate of the Libre 2 plus unexceptable. Libre 1 was a lot more reliable... I know it has been around for a while, but the Libre 2 appears to have been put to market too early and the LibreLink App needs to be tested properly.
I have even offered my services to Abbott although I am sure they won't do anything, but I have 20 years of software testing experience and can see several problems with the App and Libre system. I have identified several cases where the LibreLink App fails, but the sensor doesn't, just the LibreLink App stops reading the sensor.