Errors in pin assignment for a SPICE file in Altium
The model only has these inputs, which is only one section of the inputs for the T-flip flop. Your model has two, your sub circuit only has one.


  .SUBCKT 74HC123  A B CLR  CGND RC  Q QN  VCC VGND  


Typically spice files don't have dual parts inside of them, because they can be duplicated outside of the part. The code will need to be duplicated for both halves of the part.

There are a few options to correct this:
1) duplicate the library file and write a new one that has two of the 74HC123 sub circuits.
2) Change the graphical part to only have one flop not two. (which you probably don't want to do to mach the real world schematic)
3)  This might be solvable in the netlist by doing something like this (but I have not tried it)