Standarbank - Bank charges

Standardbank upgraded my student bank account without my consent. The upgrade caused an increase in monthly service fees, which caused huge monthly management fee as a result of the excess on the account. I logged a complain at Standardbank website on 5 Nov 2019, requesting Standardbank to reverse the charges without any penalty or negative effect on my credit rating. My e-mail address and contact numbers are correct, though I received no bank statements. Standardbank did not react yet. I am unable to visit a branch and the call centre is a nightmare...