Please note that developer tokens are only issued against production manager accounts. To create a production AdWords manager account, please follow the
Sign Up Guide. I would recommend using an incognito window of your browser when creating a new account. This would avoid any conflicts in case you are logged in to your browser with another Google/Gmail account. Once you create a production manager account, you can apply for a developer token by logging in to that account and navigating to Account Settings > AdWords API Center. Please fill the application form and then later click on Apply for Basic Access. Once you submit the Basic Access application form, our compliance team should be able to provide you with the access withing a few business days. If you do not hear back, you can get in touch with our compliance team
here. Meanwhile, you can use the developer token with test access to check how the functionality works with the test accounts. You can create OAuth credentials for test accounts by following
this guide.
Also, you would be able to download / test Campaign Performance Report via a test account as well, however, the report would not contain metrics related data (impressions, clicks, cost etc.), since test accounts do not server ads. You would be able to retrieve metrics related data in a report only when the report is run against a production account.
Hope this helps. Please revert if you have additional questions.
Regards,
Vishal, AdWords API Team