I'm running into the same issue, and I have all admin permissions. It is possible that this is an issue with the latest release of Report Builder, as another computer I have is running an older version of Report Builder and isn't having any problems.
Hi, Did you get installed the report builder from the adobe analytics tool section?. you should also have the respective access to use the report builder. I suggest you to check with your project admin and get the relevant access for the same.