Excluding my "end" problems whats the issues with this script?

I already know that my ends on my script are misplaced, the script isn't working regardless.

remote.OnServerEvent:Connect(function(player)
		if usingPower == false then	
			usingPower = true
			ifMaster(player)
				while usingPower == true do 
					Endurance = Endurance - 1
					wait(1)
						if Endurance == 0 then
							break 
						end
					end
		elseif usingPower == true then
			usingPower = false
			unMaster(player)
			end
		end

My ifMaster(player) and unMaster(player) I confirmed to work. its this specific script that the issue comes from. It does operate the ifMaster(player) function, but the usingPower value is not updated.