Dear retailsale2014,
Greetings from team eBay!
The issue mentioned by you could be related to your GSTIN and IEC details. Make sure that your active GSTIN and IEC details are updated in your eBay account. Kindly note that inorder sell on eBay from India, your eBay account needs to be updated with the active GSTIN and IEC details.
You may have also received the email notifying you about the issue with the GSTIN and IEC. Kindly check your eBay -> My Messages to take the next steps.
Regards,
eBay Team