Queen of Shadows - Discrepancy?

[Alla]

Hello everyone!
Just started reading Queen of Shadows. No spoilers please but answers to the following greatly appreciated:
So I am not sure if I’m missing something here but why is Celaena/Aeilin unable to use her newly practiced magic in Rifthold when Dorian was able to use his magic in Adarlan? This is bugging the lights out of me!

[Lisa]

You’ll find out more about it as you read the book. But It is strange that Dorian is able to use his magic while other Magic wielders cannot in Adarlan.

[Nathalie]

It'll be explaind later in the book as Lisa already said. But it really makes sense. The special person tells Dorian why it is like that. And Queen Maas planned it of course from the beginning and showed a way to put the little pieces together.

[Alla]

Thank you both so much for those replies! What a huge relief to know that this wasn’t just a slip up and an explanation is on the way :)!!!