BackBlaze S3 Api compatibility issues: Unable to create new bucket due to AmazonServiceException: not entitled?

With Java sdk i want to integrate my application with BackBlaze B2 cloud storage bucket but service replied with not entitled. What is the meaning of this?
Unable to create new bucket due to AmazonServiceException: not entitled (Service: Amazon S3; Status Code: 403; Error Code: AccessDenied; Request ID: null; S3 Extended Request ID: null)