My Nest has been working fine for over 2 years until yesterday. We got an E78 error code with something about aux/W2. We tried all the troubleshooting with no success. I also installed a new Echo Pop yesterday and it was having issues this morning too. That is when I noticed that my Nest was all the sudden connected to my Alexa app. I assume the Echo pop must have pulled it in. I don't want Alexa to have her nose in everything so I removed it and then my Echo pop started working correctly, but it did not fix my Nest problem, so I don't know if the echo caused the problem with the Nest or if it was just a symptom. Also when I try to trouble shoot through the Nest app and it asks for the error code, it says that E78 is invalid.
