That would be because your plan is 'pending', meaning it has not yet been approved and activated.
When your account has been approved, you will receive an email telling you your log-in details etc. You will also receive an email informing you about your initial domain registration, assuming you registered one as part of the sign-up process.
Account approval varies quite a bit, from almost instant to a few days. If you have already waited a few days, it might be worth lodging a support request via the panel and inquiring about the status of your account.
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