Gateway Authentication failed

Hi all,

i'm trying to configure a Pasword Initiated Session request for both a Windows and a Linux asset. The  configuration of the appliances should be ok since on another environment it works fine.I can request both sessions successfully and i can gather the token from SPP. But once i connect to SPS the connection fails and returns the error "Gateway Authentication failed". This happens for both the windows and linux asset. From what i could see from the logs of SPS, it seems like the SPS appliance couldn't verify the token generated from SPP.

The log error is this one: "Plugin(aa/SGAA/main.py): [ERROR] Authorization is denied for this request.; code=60094, data={"Code":60094,"Message":"Authorization is denied for this request.","InnerError":null}" -> "AA plugin authenticate hook result; verdict='DENY', gateway_user='None', gateway_domain='None'" -> "Authentication was denied"

On the net i found this: https://support.oneidentity.com/it-it/one-identity-safeguard-for-privileged-sessions/kb/4266938/gateway-authentication-failed 

Here it is said that the problem could be the DNS. Could certificates applied on the appliances be the cause? Is there any other possible cause that can generate this error?

I already tryed contacting the support but they couldn't help since this is a first configuration.

Thank you,

Simone