Sensor failed.. question about calling Dexcom

So yesterday we inserted sensor number #4 in my daughters arm and after a little hiccup during warm-up it seemed to work great. Worked all night and this morning it failed.

I want to call Dexcom, but does it matter that I inserted it in her arm? Does that nullify any warranty?

I don’t think that Dexcom has received FDA approval for using any sites except the abdomen. I do think they understand that arms and other sites are viable. When I call to get a replacement for a failed sensor, I will always tell them, if asked, that it was an abdomen site. This allows them to easily do the right thing.