Show message based on user location

I am trying to create an app where users can type in a message and other users that are close to that location physically can see that specific message. I have it halfway working where I am able to collect users location (who is creating the message) and I need help with the next part. I have two multiple list fields (additional message, loclist) in my database and would like to show the corresponding message to the visitor.

For example if visitor (user) is located closer to “address 1” then they see “message 1” and they are located closer to “address 2” then they see “message 2.” Any help is appreciated. Thanks!