Hi @opejinabdul,
This is likely occurring because points have not been moved from your organization to your project.
Your organization starts with one million points. However, these points still need to be added to projects. On https://develop.purpleair.com/ home, select the “Projects” tab. Next to the project you want to add points to, select the “Update Project” button. Near the top of this pop-up is your organization’s total number of points. Below that, you can enter the number of points to give to this project. Once that is updated, you can make API calls with your keys.
More information is available here: New API Dashboard.