The reason for the verification could be , as it looks like, you have returned to selling after a bit of a break.
Sudden selling activity raises red flags to eBay, as it could be a sign that the account has been hacked.
For security reasons and wishing to be 100% sure that it is the genuine owner returning to the account to sell. The account needs to go through verification processes.
Comply with any ID information eBay asks for, and it can take days or longer to verify some accounts, obviously eBay will not release any exact dates.
Keep checking your eBay messages if any further ID proof is required.
@mazikarol
