Apple Pay Button not showing / working

Hello,

I am facing a problem with the Apple Pay Button which is not showing.
When I switch to Safari Private Mode or disable the “Check for Apple Pay” then the button is there but is not functional if I click on it.

The shop console will give me the following error:
“Failed to load resource: the server responded with a status of 400 ()”

{
  "error": {
    "message": "Before you can start using Apple Pay on the Web, you need to first register your domain. For more information, see https://stripe.com/docs/stripe-js/elements/payment-request-button#verifying-your-domain-with-apple-pay.",
    "type": "invalid_request_error"
  }
}

Nevertheless, in the stripe settings (here https://dashboard.stripe.com/settings/payments/apple_pay) I have added the domain (without https://www. ) and uploaded the verification file to the server.
I have also removed it and added it again, didn’t change anything.
On other webpages Apple Pay is working for me…

What else can I do?
Thank you very much in advance!

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