Let's see how many don't read the post but just the title and react to that.
Stop telling us what your energy DD is or is going to be. It's just a made up number that your energy provider is using to get your money in the bank as a buffer for themselves.
If you're worried about energy (as we all are), why aren't you learning about it?
How much do you pay per unit for electric/ gas?
How much is your standing charge?
Are you on a fixed tariff or variable?
Do you give actual meter readings?
Have you got an idea of your usage? Check your bills, get a smart meter,
It's driving me a little mad, the amount of threads saying they're paying £500 a month, I can't afford it, with no actual relevant information that people can use to say- your usage is unusually high, they're putting your DD up too much you should ask for a reduction, your meter could be faulty. If you struggle with understanding it, just copy out your latest bill and someone will guide you.