Struggling to evolve Tyrogue into Hitmontop

This is in Emerald Legacy.

I have a Tyrogue at level 19 with equal attack and defense stats. If I give it a rare candy it levels up to 20 and gains 1 attack and 1 defense, keeping the two stats equal, but it won’t evolve. I can give it 2 or 3 more rare candies and the attack and defense continue to increase equally but it still won’t evolve. On the next rare candy only attack increases meaning attack and defense are no longer equal. It will then evolve into Hitmonlee.

What am I missing to make Tyrogue evolve into Hitmontop?