[BUG]Unable to set UCS as the4 source VIA API Call to /sessions/{session_id}/source

[c003466]

Describe the bug
Unable to set UCS as the4 source VIA API Call to /sessions/{session_id}/source

Returns the following error irrespective of the body format I use

{
"detail": {
"all": [
"Either ucs_file or credentials has to be passed"
]
},
"status_code": 400
}

Other API endpoints work just fine. This functionality works in the GUI

To Reproduce
Steps to reproduce the behavior:

1. using Postman to test
   url = "https://10.33.199.99/sessions/4/source"

payload = 'ucs_file=test.ucs&ucs_passphrase=abcde&as3_file=&username=&password=&host=&master_key=clsFC8lO0YDnwzeM5KkvmQ%3D%3D'
headers = {
'Content-Type': 'application/x-www-form-urlencoded'
}
3. but returns error whatever I put in the ucs_file field. Really I am just looking for an example of how to use this enpoint. I can not find example in Swagger Docs or on the Web. Reached out to dev central and F5 TAC but they pointed me here
4. See error

Expected behavior
I expect to get a 200 response rather than the 400 bad request I get at present

Screenshots

Context

• Please specify, app version:

• Latest version of Journeys tool from here

• And Platform version of the system you want to migrate.

• looking to migrate on prem F5 LTM to Azure DR LTM, currently running version 16.1.4.1