In the early days of web sites it was common to have someone else manage and host the site. We did this with a campsite reservation company. It worked well for many years. They have since stopped managing the site and being a small company we have lost the tools to host and manage. Our site remains online but we have not been able to access or update it for some time. How do you reclaim the site if those you gave it to have all but disappeared??? We still own the domain. Any help would be greatly appreciated.
Where is the site hosted and who is paying for that? Whomever is this billing contact for your hosting would be the one who would have to be authenticated as the owner to access the site/files/hosting.
If you are paying for hosting, you could contact the host, explain the situation, get yourself authenticated to gain access.
If it isn't you, who is billing you for the hosting? Are they paying for that but not billing or working with you?
Is your domain the same as your userhandle here? In that case your domain's DNS is on GoDaddy. But, if the hosting is not in your account then you won't be able to access.
What I would do is start working on a new website and then, since you own the domain, when the new site is ready to go, change the DNS to the new site/hosting. This approach would take that other party and the current outdated site out of the picture.
You would then have a new current contemporary site that you have total control over!