Broke My Site (Domain Issue)

Hi there. I hope someone can give me some help here. I’m pretty much stuck.

I had a site at domain A. It also included a blog at A/blog. The site and blog were each created as separate sites with their own backends.

I lost domain A by not renewing it in time. I could no longer load the sites or access their backends.

My hosting company moved everything to domain B.

They edited the config file.

Now nothing works at all. The sites do not load at domain B. I can’t access their WP backends. However, I can access the files through my hosting company’s file manager and so forth.

According to my hosting company, “It looks like everything that is stuck is stuck at the database level”, and they don’t offer support for that.

Does anyone have any ideas how I can fix my site? Thanks!