Took a look at your file, and the bases in your units are not in base-to-base contact. I have a couple pictures below to show you what I mean.
If you zoom in closer to your units in the file you sent me, you will see a picture like the following where none of the bases in a particular unit are in base-to-base contact with each other:
Now below I have rearranged your 4th Cobra unit to be legal, see how it is now different from the other units?
