Change all permalinks after blog move

Hi folks. I’ve run into a problem.
We had a blog located at… say.. https://www.ourblog.com
Now we’ve moved it to a friend’s hosting service and he had the space he offered named blog.nonsense.com
We set up the blog and redirected https://www.ourblog.com so it points to blog.nonsense.com. The problem is that all the internal links in the blog now read blog.nonsense.com/etc… (silly mistake, I know)

Is there a way to change all links so that they print the original domain URL (in this case https://www.ourblog.com)? (in case it matters, we’re using the Vigilance Theme)