local ChosenMap = AvaliableMaps [math.random(1, #AvaliableMaps)] not working. How do I fix this?

I'm making a swordfight game on roblox currently. This line of code is giving me an error saying:

" ServerScriptService.MainScript:39: attempt to get length of a nil value - Server - MainScript:39 "

local ChosenMap = AvaliableMaps [math.random(1, #AvaliableMaps)]

I have looked through other problems like this and have still not found the answer.

Any help is appreciated.

Thanks!

Thanks greatneil80