If your heart rate is not registered, it may indicate that GoBe2 cannot fully establish contact with your skin. Please check the following:
1. Make sure that GoBe's strap is fastened tight enough but that it does not hurt your wrist.
2. Clean the skin under the sensor and let it dry.
3. Clean the sensor and the contacts of the band (you can use wet wipes or wash and dry the band with a towel/paper tissue).
4. Try alternating hands by wearing GoBe on another wrist for some time.