Error While Migrating site from subdomain

Good day Dropbox-Backup Devs,

I have recently purchased your plugin to be used to transfer my website form an old server to a new one, while changing the domain from “mattsoutback.com/Newsite/” TO “mattsoutback.com”.

While Using your plugin have have Successfully backed up my old site following these instructions:

Some notes about cloning and migration
To migrate or clone this website to another hosting place (another target domain),
please follow this steps:
1. Install new WordPress on target hosting;
2. Install "Dropbox backup and restore PRO" plugin;
3. In the "Setting" of plugin select the checkbox "Read all backups from dropbox cloud";
4. Start cloning/migration process;

After following the process and getting to the point of restoring it on the new server, was greeted with an Infobox saying:

Restoration: check configuration! close
You are trying to restore the backup of domain mattsoutback.com.NewSite on mattsoutback.com.
The restoration of mattsoutback.com.NewSite backup will replace all files and database of this domain mattsoutback.com.
After start this operation of restoring you can not go back, to the old state. Are you sure, you want to continue?
    Please, check the URL to be restored, if needed correct it and start restoring.
Continue?
Url
mattsoutback.com.NewSite
 Restore        Cancel

I wanted the new site to be mattsoutback.com so I first tried doing it without the .NewSite at the end.

That game me an error saying:

Website "mattsoutback.com" returned an error during operation with return:

code: 200, text status: parsererror, text: SyntaxError: Unexpected token < in JSON at position 0
To solve this problem, we need to access the system logs of your hosting/server and/or from your backup,
that you tried to create or simply send to us your FTP access data.

I then tried leave it alone and same thing, even when replacing the “.” with a “/”. No luck.

I was counting on your plugin to do this for me, because:
A. I love dropbox
B. I need a good backup solution, and with your reviews I choose you.

So far, I have my self stuck with nothing but issues.

Thanks.

https://www.ads-software.com/plugins/dropbox-backup/