Internet sometimes works

Hello. My internet has been going on and off for almost 2 months. It will work for maybe 2 days and it will randomly shut off, then it will randomly come back on.When its off the dsl light will either be would green or flashing green and red. The wlan light and the lan3 light are always solid green. We reset our router to see if that will bring back the internet and sometimes it will bring back the internet for a few days or maybe a minuter or not all. I am wondering how I can fix this problem or maybe if its something wrong with my provider