EBS upgrade to R12.2 prerequisite checks error

Hello everyone,

i am upgrading from ebs r12.1.3 to r12.2, after all prerequisites are done i initiated the rapidwiz but on getting to the pre install checks some errors came which are almost due to database connection. here is a shot

each have this

Technology code level check:  database connection not available hence technology code level check could not be run.

DB version check:  DB version check has failed, database connection could not be established.

Database name validation: DB connection could not be established, Hence this check could not be done. Ensure that database SID given and the database name (select value from v$parameter where name = 'db_name' ) are the same to proceed with the upgrade.