This spell is simple, yet very effective, and even more effective with a pendulum if you have one on hand. This isn't my spell, but it's one I've been using for quite some time.
Think of the item you are missing, and chant:
"Bound and binding, binding, bound,
what once was lost, shall now be found
let what is mine return to me,
bound and binding, binding be."
If you have a pendulum, you can now ask it to seek what has been lost, and allow it to lead you to the lost item.
Super simple! May you find all your lost items - or ask the fae kindly to give it back...