Light post not working?

My outside light post is not working. We've changed the light bulbs and tested the light sensor. There has not been any digging that may have cut underground wires. The light post is powered directly from the house but it does not have it's own circuit breaker. When we put a new fixture on the post last year, we had to shut off all the power in the house to change the fixture. My house/development is 9 years old if that helps to know. Any suggestions on how to fix this? Would we want to call an electrician or our electric company? Thank you.