Yeah I have been using verizon Message+ and it was fine until the latest update in late January, early Feb. I use a moto360 watch to receive text notifications. Message+ kept pestering me with "calling setup" notifications, like 5-6 every day. Then just 3-4 days ago it flat out stopped sending me text notifications all together. I didn't try sending group messages during this time frame, but certainly as recently as mid-late January I was sending and replying to them.
I have since deactivated and shut down Verizon Message+, and now use Google messenger. No complaints, works great. It will send group texts, you just select multiple users from your contacts, or add a phone number for someone not on your contacts and send away.