Hi,
As far as I know the dropdown menu is validation data, did you mean you cannot use the drop down list in Excel online? Or the local Excel app?
Could you provide a sample or screenshot about the problem list?
Did this problem appear in all files or specific file?
I suggest you check if the dropdown list is created by macro or validation data, this might be the reason of your problem.
Please be a bit more precise to explain your problem or you can upload a screenshot so that I can get more accurate solutions to this problem. I’m glad to help and follow up your reply.
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