I'm trying to use the new Guidestar Essentials API but have ran into some trouble that I can't seem to overcome. I'm able to successfully make calls using Curl and via Postman, but when I try to make a call using the fetch API I get some weird behavior.
If I don't add the required headers using the Headers() interface for content-type and subscription-key, then as expected my request goes through with the POST method and receives a 401 error telling me I am missing my key.
If I DO add these headers however, then my request goes through with the OPTIONS method, which I believe means it is a pre-flight request to check that the headers are acceptable. However, this receives a 404 response! I can't seem to figure out why, and have tried just about everything I can think of in how I'm using the fetch method. Is there something going on with the API's end that would be causing this?