Space station RCS problem

So I’ve got this MASSIVE ssto that I’ve been building. It has a cargo bay on the inside (not the part it’s several thin fuselage parts that make up the walls). So basically there is a bunch of docking ports on the floor that I can use to attach anything I want using docking ports (I just rotate the docking ports and attach each other to the docking part. So I have a space station inside with what is basically 2 hulls, 1 connector between the hulls (this has a powerful gyroscope because it will be the center of the craft when it’s put together), and 4 Parts with batteries and 4 solar arrays each. Now I have a problem. RCS. So basically the problem is that the 2 main hulls which have command pods and plenty of rcs fuel and rcs thrusters, don’t work when I detach from the main ssto. Even after i switch to it and make sure the rcs activation group is activated it still doesn’t work. Now there’s sort of a second problem too. The center part works perfectly and is fully maneuverable once detached. once I manage to dock the center piece to one of the side hulls, only the center parts rcs is working even though it is attached by a docking port. This has been frustrating me for multiple days and I can’t find a solution. If anyone knows how to fix this please let me know. Should I use decouplers instead of 2 docking ports?