Gas bill has sky rocketed, what is consuming this much?

Sorry, poorly worded title but my gas bill has shot up alarmingly recently and it's getting to thr point where I simply cannot afford to pay it. According to my provider I have used 3768kwh since 1st Jan alone. I live alone in a 2 bed property, have a smart meter and have been here for 15 years and always used more electric than gas.

I've started tracking my daily usage through the app and have noticed its clocking around £8-£12 per day when the property is unoccupied or when there's low consumption (ie a no heating, no cooking at home day).

On days when I do use heating or cook etc its hitting close to £20 a day.

I've had 2 independent gas engineers rule out leaks and there are no appliances that are constantly running that use gas.

My energy providers response is "yes it is unusually high consumption but unless its a leak, it is what it is". What are my options realistically as they are refusing to budge.

Update: thanks all. I will rule out a hot water pipe leak first, and then try my gas provider again and if they refuse to accept its a faulty meter I'll contact the ombudsman.