Don't understand this error

Question

Il le lui a refusé ? - Oui, il ________ a refusé aussi. He denied it to him? - Yes, he denied it to us too.
I thought nous comes before il in this case but the quiz says " Oui, il *nous l*'a refusé" is wrong.

Accepted Answer

Bonjour Christopher, 
You pinned the wrong lesson to your query but I think that I have found it.
It was the last quiz question of the following lesson -
Position of Double Pronouns in French - Direct Object Pronoun + Indirect Object Pronoun
 
The only accepted answer is:
nous l' /Nous l'
but I am not quite sure what you wrote. 
If you wrote nous l' or Nous l' and it is not accepted, please use the Report a problem in your correction board, as it will link directly to the error. 
If this is not possible, please let me know, and I'll send your query to the helpdesk.
I hope this helps!

Answer

The subject comes first, which is il. Nous is the indirect object (refuser qqc à qqn) that replaces à qqn. Le is the direct object, i.e., the thing that is being refused. Putting it all together:Il nous l'a refusé. -- He denied it to us.