I have installed Zoiper on my Windows Phone 8.1 (MS Lumia 640XL). It works ok.
Now I want to add G.729 codec.
I go to Settings => Premium Features and see G.729 codec option/switch as if enabled.
However, G.729 codec is not actually activated.
I do not see how I can buy it.
If I click on Zoiper Gold button, then I see the following: "You have purchased Zoiper Diamond - 50E".
Is it a joke or what?