Processes in Microsoft 365 Insider for installing preview builds, activating subscriptions, and keeping apps up to date with the latest Insider features.
Hi Sujit
If your having problems with the Office Insider Fast version 16.20 (181113). I suggest you report it to them as if there is something going wrong they can fix it. We are just volunteer moderators you'll need to contact the correct team for a resolution.
https://twitter.com/officeinsider
https://answers.microsoft.com/en-us/mac/forum/m...
Hope this helps
Regards,
Sam