You need a database backup from the old host, which you will then have to restore into an empty database on the new host. By the way do not try to "move and upgrade" at the same time. Copy all your files and the database from the old host to the new host, get it working again, then upgrade. Longer that way, but if "move and upgrade" fails how will you know where to start fixing it?

EdB wrote:

You need a database backup from the old host, which you will then have to restore into an empty database on the new host.

How do I do that please?

if you have access to your databases, via phpmyadmin or cpanel or whatever they use; go to mysql databases, choose your db, then export, save as file, that's it.however do not forget to have a backup of all of your files under public_html or else it has no use.after backing up both db and files properly; you have nothing to worry about, you can rollback whenever you want.If you dont have access to those databases or you dont know how to have a copy of, ask your provider to take one for you.cheers