A woman who claims Barclays’ will-writing service cost her hundreds of thousands of pounds is taking the bank to the High Court after the Financial Ombudsman Service ruled her claim fell outside the scope of regulators.

Tinuola Aregbesola alleges the bank’s £90 will-writing service failed to advise her late father to serve a notice of severance to ensure she received 50% of a property valued at £800,000.

The Financial Ombudsman Service has ruled against the bank, but later it admitted the claim fell outside its remit. Barclays did not comment.