Even though you pay your invoice for your domain name, you might not actually own it. The key question is, who is the legal owner of it? Whoever that is has full control over which website it’s linked to and could actually sell it.
As a web developer, when building a new site I usually recommend clients register their own domain names as it keeps things simpler. I can register domain names for clients though and when I do I ensure the registration details are the clients and not mine.
How to find out who owns your website’s domain name
For .uk domain names go to the WhoIs database and search for your domain. The contact information listed for both the Registrant and the Administrator, including email addresses, should be yours. For non .uk domain names (.com etc.) you’ll need to visit here.
What if it’s not registered to you
If not then I recommend you contact whoever registered it for you and ask them to change it.
If you have any questions about this, or any other website question, please do get in touch.