HOW LONG MUST I WAIT

I apply for credit increase on my credit card on 06/01/2016. I was informed that it could take between 5-10 days. I was also requested to send my last 3 months payslips, which was done on 07/01/2016. Every time I phone the call centre the agents \are extremely"busy and the call could take more than 5 minutes. This caused that my airtime on cell phone was finished. I phoned a few times and @ time I was informed it could take another 5-10 days. Luckely I ended up with Phumla Khati"