Principal Propagation does'nt work

Hi all,

when the user using the virtual data models makes a call to ECC from SCP cloud foundry using the destination with principal propagation, the call does not reach sap and gives the following error: token validation failed:
com.sap.core.connectivity.tunnel.client.sso.InvalidSSOTokenException: Unable to verify trust for JWT principal propagation due to:
at com.sap.core.connectivity.tunnel.client.sso.cf.JWTValidator.validateToken (JWTValidator.java:80) Can you help me? Thank you