Suddenly unable to send MMS over WiFi

[Android Central Question]

I’m using a Pixel with TracFone BYOP SIM. Up until very recently I’ve been able to send MMS over data or WiFi. Now, I can only send or receive MMS when not connected to a WiFi network. However at times, if an image “doesn’t send”, the person on the other end confirms they got it anyways. Other times it just doesn’t send on their end either. The only way for it to actually send and show up on my end is to turn off WiFi before sending or mid-send. I know with how particular this sounds it may be hard to get help with it but I figured why not give it a shot and ask.