Hi Andre416,
I'm glad to hear you regularly save a backup of your file and using the scheduled feature is a great idea. It'd be beneficial for an agent to take a closer look at exactly how you've got it set up, just to make sure everything is in line and no steps have been inadvertently missed.
I also recommend taking a look at this post from another community member to see if it fits your situation. This user wrote: Scheduled backups are NOT working in Windows 10 after upgrading to the latest Creators Update, 1709.... There are a number of comments from others that may help your situation.
If you'd like to review it, here's the article for creating a backup of your QuickBooks Desktop company file.
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Enjoy your day!