MMS message say It's converting but won't send

[softballlady14]

I have and LG G4 and I am in a group message of about 20 people. I want to type in group message but I won't let me sent any messages. A popup says converting to multimedia message for group messaging but I can never sent it.

 

[Laura Knotek]

Do you have mobile data turned on? MMS requires mobile data.