I haven't used my bike computer in a while and I'm planning on putting it on my new bike. I mounted it and the computer is alive and it works, but there is no response/speed displayed as the magnet passes the sensor. Yes, it is close enough and it even makes a clicking sound as the magnet passes. It just doesn't show the speed. Has anyone had this issue or know what I could do to fix this? I'd rather not buy a new computer.