To renew the gmail token, please follow the steps below:
Edit the account settings, and click on the green button, this will bring a new popup windows.
You may receive the warning shown below, click advanced, and then click the link Go to Urban Seller.
Click allow to grant permission to Urban Seller. After few seconds the window should close, and the token is renewed.
After few minutes, you messages since the last sync should appear in your inbox, and you should be able to send emails out again.
In case of any issues, please reach out to us on Live Chat.