In Roblox, how do I check if a player is playing in a different server of the same game?

I am trying to add a /setdatabyuseridcommand. The way I do it is by checking if the player is in the server and directly changes the variable if they are playing in the server. Else just directly changing the datastore directly. My data system is loading it into a variable as soon as the player joins, and saving it when they leave. The problem is if I run this command from server A while they are playing server B, things can get really wack. Is there a way to call functions from another server?