In a new PSA first greeting should be short, as "Welcome to SFI.Ja I sponsor you and I'm here to help you ocnete this job."
Immediately after that, send a message with a short upstvom to start posla.Desava that the new PSA wants to work but do not know where to contact your sponsor because he can not find his way to find where to write the message, and question your sponsor and co-sponsor.
I hope my answer helps.