False Equivalence
#False Equivalence SayingSaying that it would require a 3rd level spellcaster to make the Common item does not mean it is a 3rd level spell.
It's a magic item that isn't producing a spell.
##It's a magic item that isn't producing a spell. AsAs you quoted, dispel magic removes the effects of a spell of 3rd level or lower. It ends spells and spells only.
What happens to your spell slot?
##What happens to your spell slot? This question handles invalid spell targets, but the crux is the optional rule in Xanathar's that would suggest the loss of spell slot.