This animation handler works in studio but not in game,how can fix so the server is able to play it?

Click play in studio, go to the explorer window, look inside your character model, and copy the "Animate" script. Click the stop button and paste the script into StarterCharacterScripts. By copying the script with the name "Animate" and putting it in StarterCharacterScripts, the default Animate script will be replaced. You can now modify the Animate script and put in your own asset ids.

There should be a part that looks like this:

local animNames = { 
	idle = 	{	
				{ id = "http://www.roblox.com/asset/?id=507766666", weight = 1 },
				{ id = "http://www.roblox.com/asset/?id=507766951", weight = 1 },
				{ id = "http://www.roblox.com/asset/?id=507766388", weight = 9 }
			},
	walk = 	{ 	
				{ id = "http://www.roblox.com/asset/?id=507777826", weight = 10 } 
			}, 
	run = 	{
				{ id = "http://www.roblox.com/asset/?id=507767714", weight = 10 } 
			}, 
	swim = 	{
				{ id = "http://www.roblox.com/asset/?id=507784897", weight = 10 } 
			}, 
	swimidle = 	{
				{ id = "http://www.roblox.com/asset/?id=507785072", weight = 10 } 
			}, 
	jump = 	{
				{ id = "http://www.roblox.com/asset/?id=507765000", weight = 10 } 
			},--- ...

Replace those asset ids with your custom animation asset ids.