@Shukran ,
In my opinion, this issue may be caused by Grammarly add-in.
I would suggest you press Win + R at same time, open Run dialog, enter "winword /a", press Enter to run Word in "administrative installation" mode which prevents add-ins and global templates from being loaded automatically.
Then please open a new document to check this issue.
If the issue does not persist, Grammarly add-in may use macros, please go to File > Trust Center > Trust Center Settings > Add-ins > Disable all application add-ins.
If the issue still exists, it's best uninstall Grammarly on one PC to have a check.
Any questions or updates, please let me know.
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