Hey @DaniCharry11, and welcome to the community.
Hope you're doing great!
I'm sorry to hear this. Can you make sure that your payment card is valid? If it is, can you try processing payment using a different browser or incognito mode?
If that doesn't help, please send me a screenshot of the error message being shown. Make sure to hide sensitive info when posting to the community.
Keep me posted 🙂
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