Help about A Chassis

Hello, I have been developing an articulated bus, but my A Chassis won’t work and just messes up the whole bus.
This is my first articulated bus so I haven’t got any idea why A Chassis wouldn’t work.
It won’t drive, walking inside it just makes it go crazy, and as you can see the wheel goes somewhere…
(Probably something related to it having more wheels, idk that’s why I’m here)
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