Hi Bijoy,
Thanks for posting in the community.
According to your description, I assume you mean the Select Data Source window in the screenshot. If so, it works well on my side and I would like to collect more information.
- May I re-confirm whether the dialog box will pop on when you click Chart Design > Select Data?
- Does the issue exist a specific document or all documents? You could create a new document to test.
- Your Office version
Click File> Account, take a screenshot including Product Information and About PowerPoint
If my understanding conflicts your meaning, please describe more details about the issue.
Regards,
George