Coupon not taken into account

Hi !

When I was asked for my subscription's renewal, I received the invoice with the coupon but not how to use it. The result is that I was charged without the reduction. It should be far more explicit on the mail on how to use the coupon ! Then I spent hours trying to send a message to a billing service but apparently there's none so I sent a message to the commercial service.

Now I lost 56 € unless Zoom pays me back !

I'm furious and I just canceled my subscription for next year !

Best regards to everybody from France !