Can't use crafted item

Hi i used the crafting bench to add extra stats on my shoes and now they are red and can't be equipped.

I read online to use an item to remove it from the item however i still can't, equip them.

What can i do? And how do know if this will happen before using the crafting table on an item?

You could've crafted a thing that has higher lvl requirement than your character is

The crafting bench has a level # next to the craft that indicates what level you need to be in order to use the crafted item.