Hi
These parameters should have been set during instance installation.
Check if these parameters are set
set lines 200
select INST_ID, NAME, substr(VALUE,1,6) from gv$parameter where NAME in ('instance_number', 'thread');
You could try to set them running the here under commands on every node, and restart instance.
alter system set "instance_number" = 1 scope = spfile sid='PP1001';
alter system set "instance_number" = 2 scope = spfile sid='PP1002';
...
alter system set "instance_number" = x scope = spfile sid='PP1xxx';
Also make sure thread parameter is set with the same value as instance_number
Regards