Buyer says only shipping label was received, tracking says refused.

I’ve been selling on EBay for about a year now and have never ran into an issue like this before. I shipped out an order last week and I get a message from the buyer today saying that USPS informed them that only the shipping label was sent out, no package included.

I go and check the tracking for their order and it says that the order was out for delivery at 7am this morning, however the delivery was refused by the addressee and is being sent back to me at 9am. I’m not quite sure what to make of this. I shipped out the order in its entirety, USPS tracking shows that the order was out for delivery but that the buyer refused the order. And now the buyer is saying that USPS reached out to them saying that only the shipping label was received. Should I be worried that I’m potentially getting scammed right now? Is it possible that the buyer took the item out of the package and then refused delivery? That seems like it’d go against USPS’s policy, but I’m not sure. If any other sellers have dealt with anything similar or have any thoughts on what might be happening here then I’d love to hear it because I’m genuinely so confused?!