Ms Dalziel had informed her local Santander branch in March that she was transitioning from a male to a female, and provided the bank with her new deed poll papers. Apart from altering her gender on its records, the bank appears to have made no other notes on its files.

Bungling Santander then made matters worse by telling her that the only way Ms Dalziel could unblock her bank account was to take a form of photographic ID into her local branch. At the time of the incident, however, her passport was in the process of being replaced with one that carried her new name and gender.

Ms Dalziel was forced to borrow money from family. After The Telegraph intervened her bank account was unblocked and the bank apologised.

Ms Dalziel has since been told by Santander that an alert has been added to her account to notify bank employees that she is transitioning.

Ms Dalziel said: “While I can see why this happened, it has been stressful. I haven’t had access to my money and have had to borrow to get by.

“I personally told the bank that I was transitioning and gave them my new deed poll papers, so they knew of my situation. I hope this doesn’t happen to other transgender customers.”

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A spokesperson for Santander told The Telegraph: “We apologise for the service Miss Dalziel received. We work hard to support all of our customers and realise that this time our service fell short.

“Last year, we worked with our contact centres to develop a process to support customers who are transitioning.

“Unfortunately, the process was not followed and we caused distress and inconvenience. We have offered Miss Dalziel a gesture of goodwill and since being able to verify her identity correctly we have unblocked her account with immediate effect.”