We just moved our API domain to another domain. That's why it's working well now. I have the same opinion, maybe their system is cached but it's affecting our business. And if you get declined one time, they're not responding to you quickly again.
They're just clicking the decline button, and its affecting our business.
Does your api use theses paths as well ?
Only the path '/download' seems affected. I don't understand why your api would use that though.