If your boiler is not working, in the first instance please check whether the boiler is turned on, and does not need to be re-pressurised (see video clip below on this).
Please also check that the failure is not due to unpaid bills/credit meter, or issues with the supply of gas/electric in your area. If the boiler cannot be turned on, or if there is no hot water/heating after the boiler has been turned on and enough time has passed to heat the water/radiators, then please report your issue to your agent.