cascaded standby issue

Hello,

I am having issue to create a cascaded standby node with the duplicatie command.

I stopped mrp and login to  RMAN to the local standby.Then I ran the following:

RMAN>

run {

  allocate channel prmy1 type disk;

  allocate channel prmy2 type disk;

  allocate channel prmy3 type disk;

  allocate channel prmy4 type disk;

  allocate auxiliary channel stby type disk;

  duplicate target database for standby from active database dorecover nofilenamecheck;

  }

RMAN-03009: failure of backup command on prmy1 channel at 04/01/2016 04:15:13

ORA-17628: Oracle error 19505 returned by remote Oracle server

continuing other job steps, job failed will not be re-run

channel prmy1: starting datafile copy