Hello & Welcome to Just Answer,
Sorry I didn't see your question earlier and to hear of any issue you are having with your device.
To help you with this issue, may I ask:
1) The FULL Model NAME/Number of the device you are working with?
2) The AGE of the device?
3) Has this device EVER found and displayed ANY course at all?
4) Are you NEAR the course at this time, or trying to find it "from a distance"?