That's odd. When I drove out to Wyoming from Philly, all the red states (except for Indiana) had almost only roaming available to me outside of major cities (including WY which has the worst connections outside of Verizon).
You may want to say what phone you have to see if maybe it's the fact that your phone doesn't support the bands available in MO.
It will probably help others see what's available out there.
If I had to guess, I'm guessing the area may not support 2G connections for voice. Where I live in Philadelphia, I had an Asian phone (Nokia 950) where the second SIM wouldn't work on AT&T because they turned off their 2G radios (or they were offline) for voice. Maybe that's it?
Welcome to our Support Community! Let's figure out what's going on with your domestic roaming. To start, can you share with me what type of phone you're using and the zip code you're usually able to connect to other networks in?
Hey there! Did you still need help getting connected out there in Missouri?