I am trying to connect GoogleAds Api using php for fetching campaign names & cost. Here is below my response of the call:

"@type": "type.googleapis.com/google.ads.googleads.v14.errors.GoogleAdsFailure",

"errors": [
                    {
                        "errorCode": {
                            "authorizationError": "DEVELOPER_TOKEN_NOT_APPROVED"
                        },
                        "message": "The developer token is only approved for use with test accounts. To access non-test accounts, apply for Basic or Standard access."
                    }
                ],

Try to get GoogleAds campaign name using customers id.