I am new to Visible, I just switched over from Verizon. When I am not connected to WiFi, my iMessages do not send at all. I read another post that said to try rebooting my iMessage settings and then my phone, but after I did both of those I'm still having issues. Not sure if at this point it's something with my phone, but any help is appreciated! TYIA!
Not sure if you got past your issue yet, but this post helped me get past a slightly different iMessages issue. For me, everything was being sent as a SMS message. My iMessages Send & Receive setting had updated after switching carriers. I had to make sure my Settings -> Messages -> iMessage Send & Receive was set to my phone number. Maybe it's worth a shot to check?