UC refused backdate on carers element any advice

Hi there I started claiming carers element for my 5 year old daughter who receives middle rate care I asked for a back date but they refused saying

One of the conditions for claiming Universal Credit following a change of circumstances

is that it is reported within a prescribed period. You must tell us about your change of

circumstances before the end of the assessment period in which the change occurred.

You reported a change that happened on 23/2/24. This declaration was made outside

the assessment period in which the change happened.

The decision maker has reviewed the reasons for the delay in notifying the change. On

this occasion it has been decided that special circumstances do not apply. Your

Universal Credit will only be adjusted from the assessment period in which you

reported the change.

I'm guessing they said no because "not knowing that I was entitled to it" is a good excuse.

I know people who have gotten a yes from the decision makers for the exact same reason which I am confused about any advice on what you do?

Thank you for your time and advice in advance