Gearing Retainers...

[RiversideGuy]

I only have 2 copies of the chest 620 DoL gear... one is equipped on one retainer and I can NOT equip the other one to another retainer. BUT somehow I managed to do that with the 590 gear, I have 2 of that, each one of the 5 equipped to a different retainer. Trying to equip that second 620 one from my Armoury chest or my inventory, same results, will not equip.

Oh, I have NONE of that gear on my in-game MIN/BTN. They have all crafted gear.

[Toutatis]

I only have 2 copies of the chest 620 DoL gear... one is equipped on one retainer and I can NOT equip the other one to another retainer. BUT somehow I managed to do that with the 590 gear, I have 2 of that, each one of the 5 equipped to a different retainer. Trying to equip that second 620 one from my Armoury chest or my inventory, same results, will not equip.

Oh, I have NONE of that gear on my in-game MIN/BTN. They have all crafted gear.

I have no issues with that. Maybe it's because you have a duplicate of the set piece you are trying to replace in your inventory. To be able to equip the 620, you have to be able to unequip and place the other piece in your inventory.

[MistakeNot]

I only have 2 copies of the chest 620 DoL gear... one is equipped on one retainer and I can NOT equip the other one to another retainer. BUT somehow I managed to do that with the 590 gear, I have 2 of that, each one of the 5 equipped to a different retainer. Trying to equip that second 620 one from my Armoury chest or my inventory, same results, will not equip.

Oh, I have NONE of that gear on my in-game MIN/BTN. They have all crafted gear.

Do you get an error message of some kind when you try to equip the gear to your other retainer? If you do, what does it say?
And just to check the obvious, the retainer you are trying to equip the gear piece to has the right class/job and the right level for it?