help in reporting identity theft in the UK

Does anyone know where I can report identity theft in the UK? I am a UK citizen and found someone with my same names and date of birth and is obviously an imposter. This was noticed when I applied for a driving license and was asked if I live at a particular address ( which I hadn’t).

I investigated the address online and saw the occupants name and date of birth as mine.

I reported to ActionAid who said they can only act if I had lost money, of which I haven’t (checked my credit history too and its ok).

Do I have to wait till I lose money before someone acts? Any idea whom I can report this too in the UK who can and will act?

Thanks