How come the mods on my Acc. Charm aren't being added to my character?

The Accessory Charm is an additional Equipment slot reserved for a second charm. The Accessory slot however does not reflect stats that are on that charm, with exception to Enhanced Effect. Efficiency is reduced by 25% of the total displayed. This charm is used just like the main charm slot and is not reflected by your total inventory space restrictions like the rest of your equipment.
In the inventory, it is abbreviated as Acc. Charm

http://ladderslasher.d2jsp.org/index.php?g=1#AccessorySlot

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