I haven't reached this level yet, but based on your description, I think your mistake is in point 5. (If I assume 1 "A" and 5 "2"s, or 2 As and 4 2s, I managed to solve it on graph paper. If it's 3 or more As, I don't know.)
Yeah there is 2 As and 4 2s. The solution involves not letting any 2 be adjacent to any A.
