Disrespectful agent

I called the Nedbank call centre today 08/09/2017 and was answered by Sibahle Ntuli from Nedbank investments, she provided me with information and after insisting on speaking with her manager Phindile Buthelezi she confirmed that Sibahle gave me incorrect information. What upsets me is not only that Sibahle boldly gave me incorrect information, she was even LAUGHING at my frustration!!