Here is a python request that I know works. Just replace the placeholders
import requests
url = 'https://api2.westfax.com/REST/Fax_SendFax/JSON'
payload = {'Username': 'Email@email.com',
'Password': 'password',
'Cookies': 'false',
'ProductId': '0000000-0000-0000-0000-000000000',
'JobName': ‘Patient Results #039239230’,
'Header': ‘Results for XYZ’,
'BillingCode': 'Patient #039239230',
'Numbers1': '9702895979',
'CSID': '(970) 289-5979',
'ANI': '9702895979',
'StartDate': '1/1/2020',
'FaxQuality': 'Fine',
'FeedbackEmail': 'doug@xnegenx.com'}
files = {'Files0': open('TEST.pdf','rb')}
headers = {
'ContentType': 'multipart/form-data'
}
response = requests.request('POST', url, headers = headers, data =payload, files = files, allow_redirects=False)
print(response.text)