MMS with AT&T WiFi Calling on iPhone X (RBR50 / RBS50)

[MattyIce]

I have little to no reception at my home, which is why I have WiFi Calling enabled. The WiFi Calling connects right when I get home and stays connected, as my phone indicates. I haven't had any issues with phone calls. But, when it comes to MMS (when I text one or more people who do not have an iPhone), my phone uses cellular data rather than WiFi.

I checked the AT&T forums and they explain that WiFi Calling should still be using WiFi for MMS / group chats. But if I try sending an image to a non-iPhone user, the image is either delayed in sending or doesn't get sent at all.

Any help is much appreciated.

[FURRYe38]

What Firmware is currently loaded?
What is the Mfr and model# of the ISP modem the NG router is connected too?
Is the Orbi system operating in Router or AP mode?

What is the size of your home? Sq Ft?
What is the distance between the router and satellite(s)? 30 feet is recommended in between them to begin with depending upon building materials when wirelessly connected.

What channels are you using? Auto? Try setting manual channel 1, 6 or 11 on 2.4Ghz and any unused channel on 5Ghz.
Any Wifi Neighbors near by? If so, how many?

Try enabling Beamforming and MIMO(MIMO may or maynot be needed) and WMM. Under Advanced Tab/Advanced Settings/Wireless Settings

Try disabling the following and see:
Daisy Chain, Fast Roaming, IPv6 and Set 20/40Mhz Coexistence to 40Mhz only. Save settings and reboot the router and satellite(s).