Forward expired??

Ordered something special for my LO on Etsy and signed up for tracking updates I noticed that it said it’s been in my city’s mail facility for about 4 days, no out for delivery updates, no other updates since then and then today it says forwarding expired and says it’s being sent back to sender.

Anyone else experience this?? I gave her the correct address and we’ve been receiving mail just fine? I sent the seller a message but not sure she can do much

It’s being sent by USPS if that matters