Not able to fetch the root folders

To list the contents of a folder, you should use the /2/files/list_folder and /2/files/list_folder/continue endpoints. For the root folder, you should set the "path" parameter to the empty string "". Note that you're not guaranteed to get all of the results back in a single response, so be sure to implement both of those endpoints. Refer to the documentation for information on how to do so properly.

By the way, those are links to the documentation for the HTTPS endpoints themselves, but we recommend using one of the official SDKs if possible. Those have corresponding native methods for the HTTPS endpoints.

Also, note that by default, API calls operate in the "member folder" of the connected account, so anything outside the member folder, such as in the "team space", if any, will not be found by default. You can configure API calls to operate in the "team space" instead though. To do so, you'll need to set the "Dropbox-Api-Path-Root" header. You can find information on this in the Team Files Guide. The File Access Guide may also be helpful.