Hi Servet,
Thank you for reaching out to us. I see that you're having issues with your developer token. Could you check your developer token access by logging into your manager account, then check "Tools and Settings" > "Setup" > "API Center" and check that your developer token has "Test Access"? If so, you can follow
these steps to apply for Basic Level access, in which you can make calls against both production (active) accounts, as well as test accounts. Let me know if you have further questions.
Thank you,
Bryan, Google Ads API Team

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