"Your message to XXXX failed to send" only to MMS / Android on Wifi? Please help
When I am at the cottage (i.e. out of an urban area), I have 1 cellular bar, often on an EXT network (because of coverage area), so I am on wifi with wifi calling and iMessage enabled. When I use Messages on my iPhone to send an MMS (i.e. image with text message) to an android device (i.e. not iMessage to an Apple device), I receive the notification, "Your message to XXXX failed to send" and a red exclamation mark appears next to the text and image in Messages.
I've tried with wifi on and with wifi off to test (worrying that wifi is the problem), always with the same result. Only when I'm back in a stronger cellular coverage area (both with and without wifi) will the same message send with no problem (i.e. by pressing "try again" when I press the red exclamation mark".
I can't find any suggestions online beyond the generic Messages comments (i.e. reset network settings, turn iMessage on and off, etc...), but the problem still occurs, but only under the circumstances listed above.
Any thoughts would be appreciated. Thank you!
iPhone 12Pro
iOS 14.7
iPhone 12 Pro