Thanks @b3pio . You were right. I assumed I needed to use an account since microG FCM always failed on my previous device and it worked when adding a google account. However based on your info I found Google Cloud Messaging doesn't seem to work and that indeed allowed FCM to work without an account. Don’t know if you already got it working @Guenter but following the instructions in the link (dialing that number) fixed it for me. Thanks again!