Google led me here: https://docs.rocketsoftware.com/bundle/grv1653317862214_grv1653317862214/page/nhb1653316841876.html
The description of error code 39129 is: The account name supplied is not an account
Check your connection settings and make sure you're passing it a valid account.
I've never used the Rocket web development tools so I don't have any info on *how* to check for a valid account.