Golf Question. How do I fix my drives?

FYI I am about a 15 handicap. Lately I have been relentlessly hitting the inside of the club face on about 90 percent of my drives. It is killing me. It happens on other clubs too but not in such an abnormal frequency. Why is this and how do I fix this? When I do this I usually hit a fade, but it only travels around 200 yards where my normal, clean drive would go about 250. It is driving me nuts.