Hi @ankitadasgupta ,
Could you please share a bit more about the error message within your app?
Do you connect to SharePoint online or On-premises SharePoint Server from your app?
Based on the error message that you mentioned, I think there is something issue with the connection you created to the SharePoint connector from your app.
Please check if the connection you created to the SharePoint connector within your app is valid. If not, please consider take a try to re-create a new connection to the SharePoint connector with proper credentials within your app, then check if the issue is solved.
In addition, please also check if the Network on your side is in a good condition. If the issue still exists, please consider take a try to re-create a new app based on your SP list data source, check if the issue still exists.
Best regards,
