Opened it on another phone or computer, or in your email app's browser? That works too. Come back here, or sign in over there with the same email and password.
No email after a minute? Check your spam folder, then press Resend. Wrong address?
One last step on this device: sign in below with the email and password you just created. If your BotDesk page is still open in another tab or browser, you can go back to it instead. It has already moved on.