I have picked up and paid for item, now seller has opened an unpaid item claim to say its not

[golden_oldies2]

hi can i please have some advise , i have won an item paid for it and collected , now 2 weeks later i get a unpaid  item case put against me , i do have emails from the seller inregards to the item for  payemnt and pick up times he also emailed to say if i got home okay with the item as i was very large ,

could i have some advise what to do next thanks everyone