£5 Amazon credit for adding a backup card - Selected accounts invite only

Add a Card promotion: Terms and Conditions
This offer is available only to customers who were served an advertisement or received an email for an “Add-a-Card” promotion and only applies if you add a valid, non-expired qualifying debit card or credit card to your Amazon Wallet. To claim the promotional credit, complete the following actions:

Click the ‘Add a Card’ widget from the advertisement and enter your credit card or debit card details.
Upon successful registration of your card, the credit will be applied to your Amazon.co.uk account.
To redeem the credit, make subsequent eligible purchase(s) using any valid payment method.

This promotional offer is valid for a limited time only or while supplies last. Offer limited to one per customer account and one per credit card or debit card. Amazon reserves the right to modify or cancel the promotion at any time. Amazon Business accounts are not eligible for this offer. Failure to follow these terms, render the offer to be invalid, and the credit will not apply. This offer may not be resold, is nontransferable, not redeemable for cash, and is void where prohibited by law and in case of fraud. This offer may not be combined with other offers.

After you successfully add your qualifying credit card or debit card, you will receive an email notification specifying the expiration date of the promotional credit. Unredeemed credit will expire after that time. The credit may be redeemed on the purchase of physical products sold and shipped by Amazon.co.uk or products sold by third-party sellers or other Amazon entities which qualify for this offer.

Offer excludes certain Digital content and products, including but not limited to Alexa, Fire, and Kindle products/devices, Gift Cards, Alexa Skills, Cloud drive, Appstore, Merch (GameGear), Music, Amazon Video and paid subscriptions such as Prime, Kindle Unlimited, Free Time Unlimited, Comixology Unlimited, Blink and Personal Shopper services. Shipping charges and taxes may apply to the full value of discounted and free promotional items. Items must be purchased in a single order and shipped at the same speed to a single address. You are responsible for the final purchase price after the credit is applied, plus applicable taxes and shipping charges. If any of the products purchased with the credit are returned, your refund will equal the amount you paid for the product, subject to applicable refund policies.