I have paid for the hosting. Why is my website not working?
As you have paid for the hosting and your service became active in Your Account, you need to link your domain to the hosting: How to link domain to hosting.
After you have linked your domain to the hosting, your website will be accessible within 24 hours. This is how much it takes ISP’s across the world to update their nameservers. Only then the Internet will be ‘aware’ of your website existence.
How nameservers work and why domains don’t go online immediately
To recap, your website does not start working immediately upon the payment for hosting services. First, the ISPs across the world have to update their nameservers, which normally takes up to 24 hours.