Schwinn S350 throttle problem

Hello All,
Need help with a Schwinn S350. The problem is that I have replaced the batteries and all went great for about 2 weeks. Now after batteries were recharged several times, now when turned on, both the green and red LED lights illuminates on the throttle control and the scooter will not run. Both battery voltages are correct, and not sure how to proceed from here. Any help would be greatly appreciated.
Thanks, Phil