The issue you are experiencing with the Excel Stock Price function may be related to the RealTimeData (RTD) function improvements in Excel M365. In recent versions, Microsoft has made performance enhancements to the RTD function, which could affect how stock price updates are processed. If the function is not working, it could be due to temporary issues on Microsoft's side or specific settings in your Excel environment.
If you continue to face problems, consider checking for updates to your Excel version or reviewing any changes in your internet connection or Excel settings that might affect real-time data updates.