Great question — answering as the UphillTech team:
Looks like you have used all your usage limit for the account. So to make new requests you'll need to generate some revenue from your account. I would advice you to test your product with a dummy API that generates the same response as PA API. You may get some ideas from the tests written in this library: https://github.com/utekaravinash/gopaapi5 If you need more help you can go through this article to understand how API requests work: https://www.utekar.com/amazon-product-advertising-api-5-go-client-library-gopaapi/ Disclaimer: I'm the author of this open sourced library and it's written in Golang.
Full answer by Avinash Utekar: https://stackoverflow.stackexchange.com/a/60473258 (CC BY-SA 4.0).
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