Away Corporate refund

I was contacted by a call centre agent from Away corporate who were marketing holiday hotel etc benefits which I was interested in. The agreement was I pay R350 per month. As soon as I dropped the phone they started deducting money to the total of R2000 which is not what we agreed on. My bank account had reserved funds of R1887 the bank cant assist in which i was later deposited R1700 leaving my account to -R296 I contacted this agent and he said by Monday it will be sorted nothing. I also contacted him again via whatsapp as he gave me his cell no he didnt respond and my account is still on a minus.