I am a fairly new Eero customer. I recently installed 3 Eero Pro 6s in a 3700 sq foot home. My Eero is running eeroOS 6.6.0. I have FiOS Gigabit ethernet and consistently get 900+ Mbps up and down to the gateway. We also have AT&T cellular service, but there is almost no cellular service in our house. 

We have been experiencing two different issues. One with FaceTime video calls and another with Wifi calling. 

My daughter is on an iPhone XR running the latest iOS - 15.1. She attempts to FaceTime her friends a lot. She will often get FaceTime video calls that either drop entirely or drop video. We've tried restarting the phone, network settings. Nothing seems to work. 

My wife has an iPhone XS Max running the latest iOS - 15.1.. She makes a lot of calls through Wifi calling (it's turned on) and we have so many issues with it. Calls dropping entirely, dropping bits of the conversation, calls not going through, etc. I make some calls too on my iPhone XS (on iOS 15.1) and experience the same issues. 

I will often be on Teams/Zoom/Google Meet calls in the same room as the router without issue. So, it's been tough for me to troubleshoot. 

Are there any tips or tricks I can try to get either of these working? Has anyone else had these issues? 

Thanks in advance.