A month or two ago, I decided I needed to tinker with our phone plan. We had gotten by just fine with a very cheap plan for years, but now that I'm doing some technical writing, I needed unlimited talk time. Since we were on T-Mobile, I took a visit to a T-Mobile store in a large mall.
First Visit: I paid a penalty to end our 2-year contract early. I got a plan with unlimited talk minutes and some other features (e.g. internet for my phone), but no free phone or other come-on; it was a month-to-month plan strictly. I had to get new phone numbers but I figured it'd be worth it. When the new SIM went into my gPhone, I was told it might take some hours or even a day for it to start working, which was really inconvenient for me (...since the whole reason for the change was unlimited talk about work.) They gave me a loaner for a reasonable deposit.
Second Visit: After a week, the new number still didn't work. I went back and they said, "oops wrong SIM!", popped in a new SIM, and it basically worked. I dropped off the loaner and got a credit for the depost, no problem!
Interim: I was not satisfied with the company, since it'd screwed up for a week and not noticed. I got another deal from another company and decided to go with it, cancelling my month-to-month plan. After all, easy cancellation with no penalty is a major feature of going month-to-month.
Then the bill came. They charged me for a whole month, which seemed incorrect to me, since their phone hadn't worked for about 1/4th of the time.
Third Visit: I went back to the mall and explained the situation. After more than a half hour dickering with a voice on the phone, the clerk at the store said they were willing to give me something like $17 and change, plus tax. They just wouldn't do more. This didn't seem right to me; I did not have the use of the phone so I was not going to pay for it. They suggested I get all my paperwork and come back the next day (PRO TIP: bring your paperwork! While they must and did have the records on their computer, I was wrong to assume they would not fetishize the paper copy. Or perhaps someone in the organization would realize it'd be harder to cover their tracks if I had evidence.)
Fourth Visit: I went back with paperwork, plus some text to edit so I could get a little work done while waiting. This time it took only 10 or 15 minutes to get the correct credit. They suggested that it might take a day to work through their comuter system, which is conceivable, so I'll wait until Monday to call and pay the bill.
The End: I don't think this should have taken four visit. I understand technical problems arise but the business side of things should have been resolvable on the 3rd visit. However, I don't really care, since the money side came out o.k., I will never see T-Moble again (...unless they offer a really good deal ;-) and I got a story out of it ... plus validation of the theory that it's not necessary to complain, just be persistent with what you want!
Apply whatever moral you wish to this story; may it never happen to you!
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EDITTED:
Late in June: T-Mobile sent me a couple of robocalls demanding more money.
I had a long phone call with their customer service in which they admitted they'd incorrectly billed me for an additional month on the month-to-month contract. We settled on an amount and I paid, in the assurance that my balance was now zero.
July 6: I received a bill from T-Mobile dated June 25, 2010 demanding more money. I phoned their customer service number and had another long call. With persistence, it was eventually determined that T-Mobile just hadn't processed that a credit yet. The bill was sent out in error. I don't owe anything. My balance should be zero.
There are lessons here, but I don't think I need to point them out.