Weird transaction please help me understand if it might be a scam

[clarissamascagni]

Hi everyone! I'm writing after what is happening to one of the items I'm selling. Basically I received the notification that this person bough the item, but it is still awaiting payment, since it is an international shipping the buyer request a Royal Mail tracking number that I need to send to eBay once the item is send. The problem for me is that the emails they look really unofficial. Please help me understand if it is a scam or not since it never happened to me before. Thank you in advance!