Overcharged Phone Bill

The other night when I was checking my internet banking account as well as my credit card purchases updates I found out that I was overcharged on my mobile phone billing account. Last January 25, a customer service called me reminding of my overdue balance, "I said how come my account was on direct debit payment" (waah) my mistake, I honestly forget to update my new credit card expiry date. Anyway, everything was settled and even reverse the penalty charged on my over due bill  and my payment was processed that day.The next day when I check my internet banking I was charged again, I’m not so worried because I know it can be fixed and settled only if I contact them. But it’s been 3 days I had contacted the customer service hotline, I can’t get through its just ridiculous I’ve been waiting for like an hour trying to talk to someone, I almost memorize the commercial they have on the line while waiting . It’s not very fair while calling the hotline it has fee per minute as well. It’s ok if just a few minutes but keep trying to ring again and again just add up the time. I’ve tried to email but there is no answer yet, I also logged in online on the network provider site to check the update of billing and payment history but I don’t see the first payment whom the person charged me that day when he was updating my new credit card expiry date. I wonder why it happens like that, I’m thinking it’s just a clerical error or I’m not too sure, I'm worried now.

I need there updates for me because 100 dollar overcharged to my account is a bit much to be just forgotten. I hope they can contact me soon and everything will be adjusted or settled on my behalf.