how to delete managed node entry on nmc 19.2 databases when the managed host result already exists ?

Hello to all,
I have installed the NetWorker Management Console 19.2.1.1.Build.78 and  ran into this anomaly.

the file test.in contain the hostname  nsr_xxx.mydomain.it, and relate ddve hostname,  ddve_xxx.mydomain.it

a) register backup server nsr_xxx.mydomain.it on nmc_yyy.mydomain.it
      /opt/lgtonmc/bin/gstmodconf -s nmc_yyy.mydomain.it -i test.in -f add -k -l administrator -P password01
      Trying 1.1.1.2 ... connected.
     processing file `test.in '
     adding host `nsr_xxx.mydomain.it '
      successfully added host
      .... 
     adding ddr host: `ddve_xxx.mydomain.it'
     successfully added host

      // Closing connection ...

comment: all done, the nws server  and relate datadomain  are now manageable from the nmc

b) delete the backup server from the management console
    /opt/lgtonmc/bin/gstmodconf -s nmc_yyy.mydomain.it -i test.in -f delete -k -l administrator -P password01
    Trying 1.1.1.2 ... connected.
     processing file `test.in '

      deleting host `nsr_xxx .mydomain.it'
      successfully deleted host
      ....

      deleting DDR host `ddve_xxx.mydomain.it '
      successfully deleted DDR host

      // Closing connection ...

comment: all done, the nws server  and relate datadomain  are have been correctly deleted from the nmc

c) register again  the backup server nsr_xxx.mydomain.it on nmc_yyy.mydomain.it
     /opt/lgtonmc/bin/gstmodconf -s nmc_yyy.mydomain.it -i test.in -f add -k -l administrator -P password01
     Trying 1.1.1.2 ... connected.
      processing file `test.in '

     adding host `nsr_xxx.mydomain.it '

   / Error!
     {
     string object_type = "gterror";
     int severity = 4;
     int reason = 43;
     int errnum = 0;
     list msg = {
     int level = 1;
     string text = "Host name already exists";
     string form = "Host name already exists";
     int id = 19712;
     };
     ....

     adding ddr host:  `ddve_xxx.mydomain.it '
     // Error!
     {
     string object_type = "gterror";
     int severity = 4;
     int reason = 43;
     int errnum = 0;
     list msg = {
     int level = 1;
     string text = "Host name already exists";
     string form = "Host name already exists";
     int id = 19742;
     };
     } failed to add DDR host `ddve_xxx.mydomain.it '
     ...

    // Closing connection...

 

Problem to solve :Both the networker server and the datadomain are no longer configured in the nmc, but still appear as if they were.