Paid for “more data transfer usage” and my site got shut down instantly.?

My page was originally www.geocities.com/dinotheorist/ years ago. I thought I bought the domain name “dinotheorist.com” through Yahoo fewer years ago, so I am confused as to why when I purchased a “web hosting” package wich allowed for more data transfer usage, then my dinotheorist.com was replaced with an “under construction” placeholder page. I clicked on the button “are you the owner of this domain?” and the instuctions said to go into file manager and rename my main page to “index.html” But that was not the problem; my “main page” has always been named “index.html. Under pagebuilder which I have always used, that is required.

The other possibility I thought of is that Yahoo is somehow not the registrar of my domain name, and I am aware of attempted “slamming” practices by companies basically impersonating yahoo and trying to take over people’s domain name registrations. I followed geocities’ prompts to see who the registrar of my domain is, but that lookup page had no instrucs.