How to use REST API without needing to authenticate to server AND One Identity console?

Hello,

I'm facing an issue when trying to do REST API calls. 

I'm using Postman, and when trying to get a session cookie (authentication), I have to both authenticate twice. Once is my own username and password and once for the admin user for One Identity. Is there a way to omit the need for me using my own username and password? As the calls are being done with plaintext. 

I know if I use OAuth, I can forego all of this. But for now, I need to use the Admin credentials until I can figure out the OAuth method.

Thanks,

-Ali