A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data
Hi @Monica Bell , thank you for posting your question in the Microsoft Q&A forum.
Since you can still open and run the script, I'd focus on its workbook association. The script is stored separately and linked to the workbook, which explains how it can remain available even when that link is lost.
Turning on “Associate with workbook” creates the link. Turning it off stops sharing and removes the script buttons, while deleting a button alone leaves the association intact.
One thing I'd like to check is whether Excel for the web shows the same problem. If you're using desktop Excel, open the same workbook in your browser with the same account when it next happens, before re-enabling the association. Under Automate, check whether the script is also missing from “This workbook.”
If it remains listed in the browser, the next checks should focus on the desktop app and its version. If it's missing in both, I'd review whether the workbook or script was moved, replaced, or restored around that time.