How Do I Enable Transaction Logs?
You must enable the Transaction Logging policy, which is a global policy, to log the request and response payloads performed against an API. The policy is disabled, by default. Since it is a global policy, the policy is applied to all APIs across the application, when you enable the policy.
Important:
This step is mandatory to view the performance metrics of APIs in the Analytics tab.
To enable transaction logs
1. Click Policies in the title navigation bar of the home page and click Global Polices.
2. Enable the Transaction logging policy by clicking the 
button adjacent to the policy name. 