This one will not work, you dont have any timer named like that:
Or do you run timers in other scripts that dont show in your code?
But you have a timer named countdown in you code:
To get the timers name use: /timers
I also noticed you using the line
/timer1 0 %var msg $chan Text
You dont need / in the remote code, to hide a timer, use . infront of the timer as you did in the first timer you start
.timercountdown 1 $2 msg $chan Text