Poor customer service

We have been with your company for at least 8 years and pay over $200 a month. In that time we have always had the next up plan where we can trade in our phones after a year and upgrade. When we upgraded our phones last year we did not change anything on our plan. When we went to our local ATT store to upgrade one of the lines we were told that we no longer have the next up plan. The location manager looked back on our account and told us that the following month after upgrading when our bill was auto drafted it was canceled. We never called customer service or went into the store and canceled it. After going through all the notes on the account the manager said there was never any notes about why it was taken off and directed us to call customer service to see if they could fix it since it showed to be a computer glitch. When calling customer service we were transferred several times without anyone even trying to help us. Even though it was not our fault and we never requested it to be canceled they still told us our only option was to pay off the remaining balance on the phone. We have been a loyal customer and never had any problems before but now we are looking to switch cell phone carriers since we are being punished for something we never did. The local store manager informed us that every visit to the store and customer service call has notes on our account. If we had requested to take the next up plan off (which we didn’t) there would be a note in the account. It makes no sense why one month we had it on our plan and the next month it disappeared when the auto payment was taken out. If this is how you treat your customers you will loose a lot of business. It’s not right to blame the customer for something we never did and not attempt to help them.