Got invalid accesstoken in postman

Hii 

I am using push data set REST API to push data in every 5 secs. While I am fetching accesstoken using graphAPIs I got 200 response body with a bearer accesstoken but the accesstoken is not valid. Because using that accesstoken I am not able to handle any rest APIs of powerBI.

To verify that I visited to the powerBI restAPI lists where all the APIs are got stored and user able to perform actions for getting knowledge like how the rest APIs are working. Link - Push Datasets - Datasets GetTables - REST API (Power BI Power BI REST APIs) | Microsoft Learn.

I login on this server and I got one bearer accesstoken which seems correct.

Now to see the defference between those 2 accesstoken I have just decoded it using https://jwt.io/

After decode I got so many mismatch values like "scp" which is known as scope is not present in the accesstoken that I have got from postman and I think that's why I am not able to handle any rest apis of powerBI. But using auto-generated accesstoken I am able to handle the rest APIs.

Please let me what is the wrong thing I am doing else is there any setting of something else I missed.