Dexcom trouble on iPhone app.

I got the Dexcom in September 2019. The receiver (little phone it comes with) has always worked with my dexcom, there have been a few times it doesn’t work, this has only happened to 2 different sensors (the thing you actually stick on your skin). I have the iPhone xs max, thought maybe it had something to do with the function of the Dexcom app. I’ve also had the app since September 2019. The app only works when I first start a new sensor or when I can waste 5 minutes trying to make it work by turning on and off my bluetooth as the app says. I’ve called the Dexcom customer support a few times and they all say the same thing, turn bluetooth off and on and wait 10 minutes. I usually have nothing else connected to my bluetooth but my dexcom and I make sure it’s connected on the device list in my settings under “bluetooth”. Anyone with the same problems? Can anyone help?