PayPal Activity Integration Through REST API

[PSMPro]

Hi,

Can someone explain to me why I get below issue when I try to call "GET https://api.sandbox.paypal.com/v1/activities/activities?start_time=2000-01-01&end_time=2018-05-09&pa..." with proper settings and token? My account is even business account and not a personal! 

{
"name": "PERMISSION_DENIED",
"message": "No permission for the requested operation",
"details": {
"": "No permission for the requested operation"
}
}