Spirit goes down when changing amulets

Hello, i am pretty new to POE 2, i already did some research regarding this potentional issue, also asked in the global chat in-game, but without any proper explanation why.
So the issue is:

I play invoker monk and i know that some ascendancy points are removing your spirit that you get from your armour but that's not the case, i don't have - Lead me through Grace. I am having 4 amulets with different stats that i am changing for farm etc. however not even a sigle one of them has spirit but the issue is that with 3 of them my spirit remains unchanged - 140 but when i put the "one" it goes back to 100. Could you please tell me if its a level of the amulet issue etc?

The problematic amulet: Agony Idol Bloodstone amulet
the rest (3) with which i don't have any changing of the spirit :
Soul Braid stellar amulet
Rift torc gold amulet
Plague pendant jade amulet

Thank you for your attention! Looking forward hearing from you!

Changing my original post finally realized when I changed my amulet I had a spirit reservation skill inactive socketed onto one of my skill slots. As soon as I added an amulet with more spirit on it. The reservation skill would reactivate taking some of my spirit in reserve. I don't know if this helps but it fixed my issue knowing where my spirit was being allocated.