Problem with MMS since update to android pie

I don't have a solution for you, but I noted the same thing when I installed the beta on my S8 plus.  I thought it might just be a bug, but looks like it might have made it to the "stable" version you installed.

I rolled back to Oreo.  No MMS issues so it's not the phone.

I've had the same problem with one of my S9's.  Another thread has suggested using a 3rd part texting app, and that they are working on a solution.

This was the sentiment of an official reply from a Comcast employee.  I find it wholely inadequate!  I hope they don't hijack your thread to say the same thing, and close it from further comment.  I've been a month without MMS texting functionality...

Yes it does, but the default messaging app should work, instead of having to install a third-party app.

Xfinity did that to make the bill more. I use wifi and keep data turned off 100% of the time my bill is about $40/mo including insurance but now they charge for MMS I fo pics all day because I'm a cam model and now they need data turned on for pics so that means I gotta go to the unlimited plan instead of per gig so that will make my bill more than double after taxes.

Since it was posted that this was fixed in the last update, I've tried it with the default messages app. It now works fine with data off. I've uninstalled the Verizon messages+ app.

Can any suggest a new message app. Got my Galaxy S8 in Nov 2017. Never had a issue with sending or receiving MMS texts with mobile data turned off. 99% of time  my mobile data is off. Just use wifi. Installed the new software update today and no more MMS without mobile data turned on.