Ability Not Showing As Ready

What you were expecting to happen, and what actually happened?
Jarl #1 was on 12 mana, rest on 0. AI swapped reds and skulls, I took damage as normal, Jarl #1 filled to 15 and didn’t swap pictures to the Fire Hammer ability art; Jarl #2 got 2 mana (AI with +2 Red banner). Match continued as normal afterwards, more or less.

Worth noting that this incidence doesn’t even have the blue glow and little runes around it like we’ve seen in the past. This has no indication at all other than the mana being full.

What are the steps to make it happen again?
As far as I can tell, this is a freak occurrence - seeing as I’ve seen this work as intended basically every other time. If one were to try to brute-force it, having an AI swap skulls and mana that fills one and starts the next one (and has a banner bonus) would be the way to go.

Do you have any screenshots or video you want to share with us so we can see the problem? Attach them to your post!
Yes, below. The first Jarl has full mana and isn’t swapping to the ability picture.

I had this before. I think it happens when the troop attacks and fills its mana at the same time.

That used to happen all the time but was supposedly fixed in the last patch - I haven’t seen it for ages… Do send your screenshot in on a support ticket…