If you want to activate a newly ordered card, for security reasons, do it only after the card is delivered to you. In this case, even if the card gets to an unauthorized person, you can be sure that your funds are safe, as inactive card cannot be used.
The virtual card is active immediately after it is added.
Also, remember that the first transaction must be confirmed with a PIN code.
ZEN app
To activate your card via ZEN app, look at the tutorial below, which will guide you through the process. Log in and then go to the accounts view. By swiping up from the bottom edge of the screen, you will expand the card section view. Select the card you want to activate, then press 
.
The "Activate card" option will appear in the card details. After clicking on it, your card is fully active and you can easily make any type of transaction.
ZEN portal
To activate your card in the ZEN Portal, log in and then go to the "Cards" tab. Then select "Manage Cards". Here, click on the image of the card you want to activate, and choose the "Activate card" option. After selecting this option, your card is fully active and you can easily make any type of transaction.