Hello @Helen32,
Congratulations on receiving a Superhost voucher.
I believe with this you do need to enter the code at the checkout by clicking on 'Coupon code' near the subtotal. When you said you received a notification do you remember if that included a coupon code?
Also, for future reference in terms of contacting Airbnb, I would recommend searching here in the Community Center (using the search bar found at the top of every page in the CC)- there is lots useful information on this. Here is a link to a Community Help Guide (which includes one on Contacting Airbnb) which might be useful, it was created by host here in the CC. Also, as a Superhost there is priority support as outlined in this Help Center article.
Thanks, Lizzie
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Thank you for the last 7 years, find out more in my Personal Update.
Looking to contact our Support Team, for details...take a look at the Community Help Guides.