Unlocked AT&T S5 with KitKat not receiving group texts properly?

The phone is unlocked, running on a Cricket SIM, so no updates to Lollipop or Marshmallow :/

We tried settings from Cricket's site, and also from a post from reddit. Neither worked.

Does anyone have clues on a potential fix?

from xda-developers http://ift.tt/2d7oaZH
via IFTTT