Cannot edit or delete Name manager in unprotected sheet

How can I edit the existing name manager. My sheet is not protected with password. Still the edit and delete buttons are greyed out

Thank you

hi, mls_newbee
It seems like there might be hidden or protected sheets linked to the Name Manager. Ensure all sheets are unprotected and there are no external references in your workbook. If the problem persists, try transferring the data to a new workbook to see if that resolves the issue.

Thank you both. I could not resolve this issue. There is no protected sheet in my workbook and certainly it has references from one sheet to other.
I just created new lists and used them as drop downs.