Hii,

Make sure both containers are on the same Docker network

• Docker container hostnames resolve only if containers are on the same user-defined network.
• Plesk’s Docker extension might create separate networks per container by default.
• You need to connect both containers to the same Docker network manually.

Verify container networkdocker network ls

docker network inspect <network_name>

 Use SSH or Plesk’s Docker CLI to run:

docker network ls

docker network inspect <network_name>

Check if both containers are listed under the same network.

If not, create a user-defined network and connect both containers to it

docker network create odoo-network

docker network connect odoo-network odoo-db

docker network connect odoo-network odoo-container-name

Example:
docker network create odoo-network

docker network connect odoo-network odoo-db

docker network connect odoo-network odoo-container-name

Set POSTGRES_HOST=odoo-db in your Odoo container environment

This matches the postgres container name and will resolve now.

Also ensure the port is the internal Postgres port 5432

The POSTGRES_PORT environment variable should be 5432, the internal port, not the published port like 32788.

i hope it is usefull