how to change my licence from regular to extended?

I sent several emails to Envato help center asking how to change my licence to a extended one but have not received any reply from them.
can someone tell me if there is special site or email to asking for this?

Thanks

This option for customers only (changes in the menu on the left from the price)

I think he wants to upgrade the license from regular to extended, if I’m right, then there is no way you can upgrade it yourself, you need to send the Help Team a ticket with the name of the item and the username of the account that is associated with the purchase.

If you’ve already done that, then you need to wait a little bit more. Or you can tweet them @envato_help, tweeting them usually speeds things up.