sandbox API testing , Bad request error

Hello David, its is clear from the code you have shared that you are missing some requirements.
Forexample, the Authorization is supposed to have the word Basic at the start, there after the Base64 encoded string.
 

Kindly vote answered if true, so other developers with the same inquiry can easily find the answer.

Please share a similar request with complete request, so that i may test then respond

I found the answer in the link below, on post man

https://web.postman.co/workspace/My-Workspace~db6063c4-b8b7-4396-8de1-0a0c3a5633b8/collection/16404369-14f46d82-4701-45d4-8666-5928591c1666