Hello,
I do not know if the problem is known, even if indeed it is a bug or if this is normal but hey, I still explain.
On my Hunter I am in grimoires of 5305.
On my Titan I am in grimoires of 5190.
On my Warlock I am in grimoires of 5195.
The difference comes from sleeping siva fragment recovered from each character.
Is this behavior expected by Bungie (though I doubt it) or it's a bug well as it should?
Regardless, it does not interfere with play but it disturbed me on the spot.
Good game to all of you.
PS: Sorry if I used the wrong words for specific things in the game, I'm French and does not know all the original names of all items.