Error while trying to access Ultimate POS running on local server from multiple computers

Hello, I bought the Ultimate POS software a few months back and have been running it on the local server. Now I want to be able to access it from multiple computers connected by LAN or wifi but it keeps showing me this error message “Invalid License! Please Purchase new License. DOM”. I need help setting it up so it can be accessed from two or more computers.
My envato email is [email removed]

Contact the item author for the help/support