setting up 2 motors on one axis not working

Hey,after 2 years i am finally  using 7i96 mesa card. I am trying to set up the motors for my router and the y has 2 motors. i set up both in the pnc conf- one is the main y and the other is tandem Y2. when I then go to the motor testing and setup only one spins when I test. both motors work and when I swap around connectors everything works, including when I set them up as x y z. But when I have 2 motors on one axis only one spins. I wanted to give you the hal file but when I plug in a USB stick it does not pop-up (still very new to this). Here are some pictures. Let me know if I can give you something or how I can get the USB to work so I can download the file haha.  Thanks in advance 

Update. when i go to the linux cnc I get 4 joints instead of x y z.

Do both Y have limit/home switches?
They must be set in the wizard for each Y.

None of them have a limit switch yet.

Do not set tandem axis, it does not work without home switches.
Set it as a normal XYZ machine and wire the two Y motors/drives to the same stepgen/output, be it physically or in hal.

thank you tommy. i will try adding home switches.