Remember that you can only spend what you have, nothing more.
The Coverflex card does not have any credit option and/or use of negative balance. For example, if you have 19€ in benefit balance and want to make a 20€ purchase, the card will be rejected by the terminal. It works like a classic debit card.
What happens if the balance on my card is lower than the price of an item I want to purchase?

Edoardo Celestino