Can't seem to reactivate Gitlab Pages with the default domain

I had a page running with my default domain, somehow deactivated it switching settings around and now I can’t seem to reactivate it. When I visit the domain there is no page. In the Pages settings, where I used to see the previous default domain, I can only see the option to add a new external domain. I’ve been trying to read but cannot seem to find a solution in their linked documentation. I feel like this should be very simple but yet I can’t seem to solve it. It is rather important for me to fix this since my website is currently linked in other places and has no destination because of this issue. Please help. Thanks.