Without seeing your setup, it sounds as if you have some code running ON SAVE or ON OPEN.
If it's happening just for you, I suggest finding the PERSONAL.XLSB in the XLSTART folder, and removing it by copying it out of there, perhaps to your documents folder for future inspection. For more info, check here: https://support.microsoft.com/en-us/office/copy-your-macros-to-a-personal-macro-workbook-aa439b90-f8...
If it's happening across an organization, well...there's a gremlin running around somewhere.
