When creating users mongo throws E11000 error (E11000 duplicate key error collection: invent.users index: photo_1 dup key: { photo: null }"). I don't have the photo key anymore and deleted documents from the collection. Now, once I create the first user, I cannot create the second one. But if I delete that only one, I will be able to sign a user - but only 1 again.

So I'm wondering if there is a cache and a way to clear it because it seems that the problem comes with the photo key though I do not have it at all in my Model.

Someone says that Mongoose doesn't keep any cache, but what can it be that kept the field that doesn't exist anymore? I guess dropping the collection will resolve the problem, but this is not the best solution.

Thanks in advance!