Unable to exchange NIS with NS

I'm a Norton reseller. I currently have 35 units of unused "Norton Internet Security - 1 Year - 3 PCs" license (which can be used to activate up to 105 Devices).

Do you think it's fair to replace & exchange these unused license with 21 units of the latest "Norton Security - 1 Year - 5 Devices" license (which in total, can also be used to activate up to 105 Devices)? 

Sadly, the Norton Support via Chat say No & Impossible !!!  

Well, this is very disappointed. I am not asking for 35 units of Norton Security, this change seems to be equivalent. Moreover, NS is obviously NOT a new product, as indicated by its version of 22.x.x.x. 

If a transition option is not available, I will move to another antivirus soon. indecision