Your boiler has lost its gas supply, meaning it cannot light the flame to provide heating or hot water.

DIY fix possible

Check that your gas emergency control valve (usually by the meter) is in the 'on' position.If you have a pre-payment meter, check that you have sufficient credit and the valve hasn't closed.Check if other gas appliances, like a hob, are working to confirm if the issue is with the boiler or the whole house supply.Try resetting the boiler by turning the selector switch to the 'R' position for at least five seconds.