Hi I have aswell the same problem I get a 403 error:
HTTP Response Code: 403
The response id to help bunq debug: The response header "X-Bunq-Client-Response-Id" or "x-bunq-client-response-id" could not be found.
Error message: <html>
<head><title>403 Forbidden</title></head>
<body bgcolor="white">
<center><h1>403 Forbidden</h1></center>
</body>
</html>
It always worked (for years) and now it stopped working.