Maybe it was a book, a pair of earrings, or a lawnmower - whatever it was, you have it and they want it back.
Even if it is years later, it is never too late to give something back and apologize for the delay - it’s the right thing to do.
Still, giving something back and apologizing for taking so long to do so isn’t easy. The most important thing is to acknowledge the mistake and apologize for it.
Talking Points
I’m so sorry I’m only just now giving back your <item>.
Please accept my deepest apologies for my delay in returning it.
It was so <fun, helpful, perfect>, but I didn’t intend to keep it!
If there is any way I can make it up to you, please let me know!