Recent autopay debacle...

Like many, I chose to sign-up for autopay for the discounted charges. Everything seemed to work fine until recently.  My payment was scheduled for the 4th of every month. This month I received a text message which was very strange as it began with "Hey there! We need to get in touch with you about a recent payment made on your account...."  very weird wording - I mean they know my phone #  right? Just call me. Anyway, Before I contacted them, I went to my credit-union page and saw that, as always, the payment was credited on the 6th of the month. I then logged into myt-mobile.com and to my surprise saw that they claimed I was overdue on my payment and had tacked on a $35 late fee. 

  I called them and had to fight through their automated system insisting on speaking to a human and did finally get through to one. I was told that my payment had been canceled/stopped by my credit union - or so they claimed. This made no sense so I contacted my credit union. They showed no stop payment and also note that they had not received any return of the $ that had been paid out. They then had their operations team look into it - again, no indication that any stop payment order was issued nor any funds returned. So, I called T-mobile again and fought through their obnoxious automated system for another 10 minutes.  T-mobile refuses to provide any "proof" of the claim that a stop payment was issued.  I was effectively forced into making a second payment and am obviously out of my $ which was taken via autopay. 

  Now this is obviously a screw-up on T-Mobile's end. My credit union is fairly small and over a 3-4 hour period they literally went through every transaction made for the two days that t-mobile claims a stop payment was issued. There was nothing. No such transaction took place. Now I don't know if this was just a data-entry error or wtf is going on but now I am between a rock and a hard place. The credit union can't won't give me back $ that they have not received and t-mobile refuses to look into it and instead forced me to double-pay for this month.  

  Today they sent me a message saying that I "Authorized cancellation of recurring electronic payments to T-Mobile..."  which I haven't done but I am not going to argue with. I mean screw it - I don't trust their system now at all. I'll pay the extra $15/month to know that my payment has been made and acknowledged. 

 So has anyone else had anything like this occur? Is there anything that you can do to force them to trace this supposed "stop payment" or to find thwe supposedly returned $ that was never returned? I'm seriously tempted to switch services but really do not want to have to go through the hassle....