Trails to Azure S-Break bug?

Hi, I'm currently playing Ao no Kiseki for the first time (Switch English release) and I've noticed a strange bug. Sometimes during battles, I can't do a character's S-Break even though they have more than 100 CP and no status effects.

It seems to happen AFTER a character had a status effect which wore off. For example, if Loyd gets sealed with 90 CP, then gets to 100 CP while he's still sealed, when the seal wears off I still can't do his S-Break and the red square beneath his icon is still empty until I attack with him again.

Is this intended or is it a bug? I don't recall this happening in the other games, and I've playing all Trails in the Sky, Cold Steel games and Zero no Kiseki. Did anyone else encounter this? Definitely frustrating when this happens in a tricky situation where an S-Craft can save you.