Thanks for the advice so far.
The name concerned with the defaults and apparent Alias has my first name, my date or birth, my old address that I moved from almost 12 years ago, but uses my mums maiden name.
it's got to be fraudulent, which is why I reported it straight away.
The debt collection agency that holds the default for the credit card just told me to ring Experian and ask for the names to be disassociated as it's a different name ( Experian say they can't do that)
As for t-mobile the information they sent back to Experian say they have looked at the account and d