This functionality is only available if you are an Admin user
To cancel a card
- In the Yordex interface, go to ["Cards"]
- Find the card you want to block and click on it
- Click on the ["More ..."] menu
- Click ["Cancel"]
Cancelling a card cannot be undone and all funds will be transferred back to the master balance. If you only want to temporarily disable the card you should block the card instead. How to do that is explained in this article.