Hi

Please create a new odoo role user with another name, You can use different port numbers for different odoo versions like 8014, 8015, 8069,8016, etc...

Also, you want to set different PostgreSQL users for different odoo versions and make them super users.

https://www.cybrosys.com/blog/how-to-install-odoo-16-on-ubuntu-2004-lts

https://youtu.be/nQ73o2yKlPQ

Hope this helps 

Regards