There are serveral reasons why your battery may not be discharging to the house.
The most common reasons could be:
Battery has 0 volts and would require a force charge.
incorrect battery comms cable is being used
Wrong charging settings have been set.
If you are the homeowner please contact your installer in the first instance.
Alternatively, please contact customer services.
Email: support.uk@duracellenergy.com
Phone: 0808 281 2855 (Monday-Friday 9am-5pm)