Adress changed without my knowledge

Today I went to the Fnb atm in protea glen to print my bank statement to my Suprise my residetial adress was changed to a place where I never stayed at all I dont know hoe was it done.I have been an fnb customer for more than 20 years This was a shock of my .I phoned and complained the consulted sent an email to the relevant branch who did that but they havent respodent to me.