A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data
Dear Webbrewers,
Thanks for your confirmation.
The feature does work in my environment. There may be no other way creating the dropdown list in Excel for the web.
As the feature doesn't work in all your files in Excel for the web in your environment, I'm afraid that there may be nothing you can do at your side to fix the issue by yourself and the issue needs to be fixed by our related team directly.
I suggest you contact the administrator in your organization if you aren't the administrator and let him follow the steps in Get support - Microsoft 365 admin | Microsoft Learn to open a support ticket to our related team as soon as possible.
The administrator is always the first person who subscribes the Microsoft 365 business subscription or the IT administrator in your organization.
About admin roles in the Microsoft 365 admin center - Microsoft 365 admin | Microsoft Learn
How do I find my Microsoft 365 admin? - Microsoft Support
Thanks for your effort and time.
Sincerely
Cliff | Microsoft Community Moderator