Devotion and Enkindle problem

[Grimoire-M]

Pretty much what Chaotic said. You can't use pet abilities back to back in general, however. So you'll feel this with Contagion/Shockwave/Aerial Slash if you're manually casting them back to back with Garuda, and similarly if you do so with Ifrit for whatever reason. Enkindle/Aetherpact are notable in that any other ability can interrupt them though, even Aetherflow abilities and Shadowflare. The best thing to do is to treat them like a long animation and only use one of them per GCD.