GM Motors Do not purchase a vehicle through GM Motors Clarks Summit PA

I recently purchased a buyout on a GM Terrain> In April of 2016 I was told by GM Motors to make the buyout payment to GM Finance. I made this payment within days of the payoff request. I began getting calls by GM Finance one month later about my account being past due. They were calling me daily looking for payment on a account that was paid off. Obviously this was extremely frustrating because I had indeed made the payment and was under the impression that everything was as it should be. They continued to bounce me around to various different companies and nobody could seem to tell me why they were requesting a payment on a payoff that had already been taken care of. It has taken three months to finally resolve this issue and my credit has been seriously affected through three different credit bureaus not to mention the countless hours of NY time and well over fifty calls Trying to rectify their mistake. If that wasn't bad enough, it has taken until this past week for them to release the title to me! Never Never ever purchase a vehicle through GM!1!