Unauthorized Charges on Virgin CC Account

I received a charge on my account with the description of INET/MOB FEE/FOOI. I called Virgin Money to query this and was told to send an email to the disputes division, which I did. I have not received any feedback. If this is for internet banking, why am I being charged when Virgin Money is not supposed to charge for internet banking - it even states that on their website. I want this charge reversed asap.