✓ Accepted answer
After chatting with the user I've found two issues, One with him using studio and one with the script.
The issue with the script is elseif game.Lighting.TimeOfDay < "19:21:00" then
The issue with this is its checking if its before 19:21 NOT if it isn't 19:21
As per Lua's Relational Operators, not equal would be ~= so, it should be elseif game.Lighting.TimeOfDay ~= "19:21:00" then
The next issue is due to not knowing about a studio thing, by default when you are changing properties in the properties tab its being changed from the client side, you want it being changed from the server side since its a server script (and if it was from the client side it would only change for you due to filteringenabled) so the fix to that would be to go to the menu bar on studio and click home, Where it says Current:Client, Click it. After you click that it will change to server-sided mode so then when you change the TimeOfDay property, it will change on the server not the client, so then it will print Its not 19:21!.
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