My AST is so weak, why?

[Ghishlain]

I just looked at your loadstone, Czar D'luffy. Is your weapon updated? It's currently showing an i43 Weapon which is WAAAAAAAAAAAAAAAAAAAAAAAY too low for Dusk Vigil if your lodestone profile is true. If you need a quick upgrade, purchase a vendor one that's i110 in Ishgard. That should be more than sufficient to heal through Dusk Vigil.

That would be your main issue, though it could be compounded if the tank wasn't playing properly too.

Get a new weapon, and try again and you should see dramatically different results.

[Ashelia_Ferron]

Go cast Benefic on yourself. If you're not healing 1400-1500 then your gear isn't good enough and judging by the previous post, your weapon needs updating.