New smart gas meter faulty.

Had a new smart gas meter installed on 8th/March/2019. Went to prepare something for the family to eat but had no gas, checked the meter and it was off so I followed instruction to get it back on but it kept going off after about a minute, couldn’t get through to bulb as it already past 18:00 so had to contact cadent emergency services they said the meter is faulty, they can’t change it and that they’ll have to cap it off for safety reasons and to contact my supplier in the morning so my 1 year old daughter had to sleep without heating. How come there isn’t a after hours emergency contact service with bulb?

Even if you had got through to Bulb they would then have to arrange for a meter change so it probably would not have made much difference, time wise. The emergency services done what would be expected and that is cap off the supply.
I know it is difficult especially with a family but normally the not having heating would not be an emergency unless it compromises safety.