I was recently a victim of cyber crime. I am a retiree with a large pension pot amassed from personal investments, and a financially savvy person. I am very aware of phishing and telephone fraud schemes and can usually spot them.

However on this occasion I didn't spot the scam until it was too late. My son is studying in the USA and I am supporting him financially, so he will often ask for a little extra help. We communicate exclusively by WhatsApp.

I recently received a WhatsApp from him saying that he had lost his phone and that he was borrowing a phone from a friend. He said that he was in trouble because he needed to repay a loan and his banking app was on his lost phone.

After many back and forth WhatsApp messages he assured me he would explain everything when he gets his new phone. The 'borrowed' phone was a UK number so I didn't call it as I knew roaming charges could add up.

My son will often use my credit card for purchases with my permission, so on this occasion when he asked for the one-time password I gave it to him. About four hours later my son sent me a WhatsApp from his usual US number and it became apparent that I had been talking to someone who was impersonating him.

This is a very clever scheme because it was a Sunday and as the bank offices were closed it took some time to contact their fraud line. I locked my card online so no further payments were taken. It was also clever because most parents will drop their guard due to a desire to help if their offspring are in trouble.

If it had been anyone else I would have questioned the request. I am hoping that the bank will reimburse me after the case is investigated by their fraud department but I am not confident that I will get the money back because I authorised the transaction believing it to be genuine.

I have read of cases where victims give passwords or security details to a third party and I think, how could they be so stupid. This case shows that anybody can fall victim to these criminals.