OT: What would you do?

[Eric72]

The thread is only slightly OT. Pretend the item was a t206 common, if that helps.

I sold an item on eBay and shipped it the next day. A few days later, the buyer left me positive feedback. The feedback stated, "Properly packaged and marked for shipping..."

So far, so good.

A few days after that, I received a message from the buyer. "This item was expected to be delivered on XXXX. It still hasn't arrived..."

Interesting.

I submitted a USPS Missing Mail Search. The item was marked delivered the following day. I informed the buyer, who wrote, "It came today..."

Glad to hear that. I'm also glad to know I package things so well. You praised my packaging almost a week ago.

My question is this:
Was someone attempting to scam me? I think so, and plan to block them. I just want to make sure I'm not overlooking something innocent.