Drop down list

It sounds like Excel created a floating object (such as a text box or shape) when you made the dropdown list. Here’s how to remove it:

Solution 1: Delete the Floating Object

1. Click on the empty box. If it gets selected, it’s likely a shape or text box.
2. Press Delete on your keyboard.
3. If it doesn’t delete, try right-clicking it and selecting Cut or Delete.

Solution 2: Use Selection Pane to Find and Delete

1. Click anywhere in the Excel sheet.
2. Press Command (⌘) + Shift + Option + K to open the Selection Pane.
3. Look for any unnamed objects in the list that don’t correspond to your dropdown.
4. Select them and press Delete.

Solution 3: Check for Data Validation Input Message

1. Select the cell with the dropdown.
2. Go to Data > Data Validation.
3. In the Input Message tab, uncheck "Show input message when cell is selected".
4. Click OK.

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Hope this will help you.