Do you own your domain name?
Do you know where your domain name is registered?
You should. It's one of your primary digital assets. And if you've had a website for a while likely has a Google ranking. Loose it and you could end up starting at square one. What would that mean for your day-to-day business activities? Loss of enquiries? Invalid email addresses?
A disaster that happens all to regularly.
In all likelihood your domain name was registered and purchased by the person that developed your website. Which, is fine as long as that relationship never fails, that they are due-diligent in renewing your domain as necessary and that ultimately the domain is registered in your name not theirs!