How to make a enchantment multiplier?

Hi,

I'm making a mod and there is a table that should multiply enchants when theres these items in the slots the enchanted book you want(slot 0), book(slot 1) and lapis (slot 2)

and when you click the button there it should put a enchanted book (with the same enchant on the book in slot 0) in the 3rd slot. I tried everything i could think of but it doesn't work, heres the procedure of the button when it's clicked: https://drive.google.com/file/d/1ptxs9pr9U5Lifcss3vD0TpDvBWoNDI2e/view?…. Can someone help me? Also I put only one enchants code because there's one for every enchant and it's long.