You need to send request to get pack

https://wpsoul.com/extended-license-request/

It has a link to click and purchase 1licences i.e.

Buy +1 more
and Get 5 licenses in Total

When clicked it takes me to themeforest. 

That's is how i purchased my second license and i should have received 3 more licenses, but i haven't received them.

you can find all details when you register your license in Rehub - registration section of theme

I already have 2 licences for Rehub theme, how can get the extension for 10 licences?

I see in this in the registration page 

Buy +1 more

and Get 5 licenses in Total

______

Buy +2 more

and Get 10 licenses in Total

______

Buy +9 more

and Get 100 licenses in Total