Applying an extra cover doesn't work properly

Dogface

I have a 1* Spider-Man at 3/5/5 (red/blue/purple) and level 50. As everyone knows, 1* can't be champed, but you can apply an extra cover at the cost of another color. 

This is where the problem arises (and if I'm not mistaken, this has been brought up before).
Whenever i get a red Spidey cover, and try to apply it, it stays at 3. The cover is lost and I get no chance to change the distribution from 3/5/5 to anything else. Result is, i'm stuck with a lot of blue and purple Spideys i can't use.

The reason I want to use them is for daily quests and xp.