Building a flight with a ground network component?

Example for this question: Want my small regional plane (CRJ 900) to fly from TLH to DAL and then a ground connection to DFW which is the HUB of my airline. When I build the flight as DFW>DAL>TLH or TLH>DAL>DFW, I get the red X for Route restrictions. Others in the game world have tons of flights with ground network of a similar nature. I’m not sure what I’m doing wrong. Have a station in DAL and obviously in DFW. Help?

I have never tried a ground network so I looked through every tab and have clicked on Ground Network Tab repeatedly on DFW and then DAL. Watched video on YT that didn’t really explain and the handbook didn’t explain setup either. Read through other posts but not getting me to a resolution.

Appreciate any help,
Pie

Check the forbidden routes. You cannot fly DFW DAL. You also don’t need to - ground network is working without flights between these stations,

Thanks for replying, I’m trying to use slots at DFW for bigger flights, but want to service smaller airports in Southeast US through DAL that can ride the bus/train over and connect worldwide out of DFW on my bigger planes.

This isn’t currently supported by AS, unfortunately.