Zephyr Squad Cloud API - Error 104

I am trying to hit this API : https://prod-play.zephyr4jiracloud.com/connect/public/rest/api/2.0/executions/search/cycle/9386b6c5-6d96-4117-a2ce-3ff647b6da13?projectId=10040&versionId=15217

Generated JWT token and provided token and zapiAccessKey as per : https://support.smartbear.com/zephyr-squad-cloud-v1/docs/en/zephyr-squad-cloud-rest-api/generating-a-jwt-authentication-token-for-zephyr-squad-cloud-api.html

Getting error : 500 internal server error

{
    "errorType": "ERROR",
    "clientMessage": "We encountered some problems during processing this request. Please try again!",
    "errorCode": 104
}

Even if no value is passed in "zapiAccessKey", its the same error.. Not sure even if its even authenticating.