Hello @Sabrina H,
Would you mind sharing more details, like the OS/Illustrator version and a small screen recording of the problem, so I can better assist you?
Also, try resetting Illustrator's preferences as described in this article (https://adobe.ly/41VKbzh) and checking if it helps?
Disclaimer: Please note that renaming preferences folders will remove all the custom settings, and Illustrator will launch with default settings. You can also save a backup of the folders in case you want to. The location is mentioned above.
Looking forward to hearing from you.
Anubhav