You could try a different browser, or using incognito mode in your current one.
If that still give you problems, contact customer support through this link:
They'll help you sign up. They take, at the most, 24 hrs to get back to you.
Don't forget to check your spam folder for responses as they may end up there.
If you get an automated email directing you to the community or help pages, you need to reply directly to that email (even if its from a no-reply address) and one of the customer services agents will get back to you.
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