I can't add a product using asp net core

[JakeMurray]

Here is my code snippet. It returns forbidden.

My goal is to upload products from a csv file. Basically a batch upload.

I've tried this in postman and it added a product successfully.

I also tried the GetAsync where every field is a query. That also returns forbidden and it works in postman too.

Everything as far as I know is configured properly in WHMCS side as it wouldn't have worked in postman if there's something I forgot to turn on.

Or there might be some configuration/work-around that I might have missed?

Thanks!