Disaster recovery (DRS) oracle database troubles

[nahumcueto]

I'm using WinCC OA 3.15 Patch 007 and Oracle database 12.2.0.1.0
All the six servers are running RHEL 7 (kernel 3.10.0-693.2.2.el7.x86_64)
SQL scripts ran from a Windows 10 workstation (Windows version 10.0.17763, compilation 17763)

I'm trying to configure a DRS. First I configured both Oracle database servers and I checked I could access both from each other and from project servers (using two TNSs)

Then, I ran win_install.bat to create the structure and it finished with no errors. I checked that I still could access via sqlplus @ TNS.

After that, I tried to execute sync/SYNC_Setup.bat but this was not successful and once this script failed, I could never again access one of the databases [with the command 'sqlplus']; now it's always shown the error message 'ORA-12545: Connect failed because target host or object does not exist'. Even if I restart the database server, login has never been available back.

I attach to this post the log of the script 'sync/SYNC_Setup.bat' (passwords changed to "*****").

Why the TNS listener in one of the servers stops working? Did I make any configuration mistake? Why am I asked to input the schema user four times in a row?