Hello Laura5EB3,
Sorry to hear about this experience. I would request you try resetting Illustrator's preferences manually and see if that helps resolve the issue:
For macOS
• Close all Adobe applications.
• Go to the following locations
• ~/Library/Caches
• ~/Library/Application Support/Adobe
• ~/Library/Preferences
• Rename Adobe Illustrator, com.adobe.illustrator and Adobe Illustrator 25 Settings folders to Adobe Illustrator.old, com.adobe.illustrator.old and Adobe Illustrator 25 Settings.old
• Launch Illustrator from the Creative Cloud.
Note: Location starting with this "~" sign indicates the User Library, which is hidden. So, you need to copy & paste the exact path in spotlight search or from Finder Menu > Go > Go to Folder > Paste the location in the dialog box like this:

For Windows
- Close all Adobe applications.
- Go to Location C:\Users\%USERPROFILE%\AppData\Roaming\Adobe
- Rename Adobe Illustrator and Adobe Illustrator 25 Settings folders to Adobe Illustrator.old and Adobe Illustrator - 25 Settings.old
- Relaunch Illustrator
Disclaimer: Please note that renaming preferences folders will remove all the custom settings, and Illustrator will launch with default settings. You can also take a backup of the folders in case you want to. The location is mentioned above.
Looking forward to your response.
Thanks,
Anubhav