Galaxy S9+ won't send MMS messages
I activated my S9+ at a Boost store this week. The phone was reset before activating service.
Using the Messages app it will not send a message as a reply to a group text as MMS and will not send a photo via MMS. Send group conversation is turned on. I noticed the Access Point Name on the phone is T-Mobile.
I don't know if it matters but when connected via wifi the mobile network state shows as disconnected. When off wifi it shows as connected. The phone will not send MMS either via wifi or mobile data.
Mobile data has been turned off and on as well as the phone power cycled.