Installer is not giving options to install the postgresql

Products

• CA Application Performance Management (APM / Wily / Introscope)

Issue/Introduction

Operating system in use : 

NAME="SLES"
VERSION="15-SP4"
VERSION_ID="15.4"
PRETTY_NAME="SUSE Linux Enterprise Server 15 SP4"

The installer is not giving options to install the postgresql rather it give me to upgrade.

Following is what the selection I got and it keep returning to this screen

information. Choose to deploy the APM database on PostgreSQL or Oracle.

  ->1- PostgreSQL

    2- Oracle

ENTER THE NUMBER FOR YOUR CHOICE, OR PRESS <ENTER> TO ACCEPT THE DEFAULT:

Environment

• Release: 10.8

Resolution

PostgreSQL installation is not part of the CA APM 10.8 installation and must be installed before you start the CA APM 10.8 installation.

Postgres is a third party product and you need to download and install it on your server before installing APM.

APM Database is not Postgres, it's just a Database the APM installer will create in Postgres.

Install and Configure the APM Database