Honeywell programmable switch: lights always on...?

I have a Honeywell programmable switch for outdoor lights. Recently, I realized that even when the switch is supposed to be off (during the day), the lightbulbs are not completely turned off. They are much less bright than during the night but there is still a noticeable light… Thus, I am assuming something is wrong with my switch… Has anyone encountered this issue ? Is there any way to reset the switch ?