Product: Credit card

On the morning of XX/XX/2016 my son received a call from someone claiming to be the FBI. They knew a lot of his personal information and threatened him with arrest. He was bullied and threatened so he went along with the callers. At the end of the day our credit card was charged XXXX. 
My husband received a call from Chase on his cell phone while in a meeting, he saw who it was and answered. He was asked if he knew my son, he responded yes he is my son. 
My son was being forced to spend an unusual amount of money so Chase declined the cars. My son was told to lift the block on the CC, he did try but did not remember the answer to the security question. This is when Chase called my husband. 
He was asked if he knew my son because he was spending a larger than usual amount of money. My husband responded, he is probably buying books for school. 
At no time did the associate say the purchases were being made at XXXX and XXXX, if he was aware of this he would have known there was a big problem. The purchases were all made to purchase XXXX cards total amount of XXXX. 
When my son realized he had been a victim of a scam he called me very upset and in shock. We both tried to call my husband but he was in meetings. 
My husband returned home that evening to open his personal email, he then saw there were three email from The Fraud department of Chase asking him did he approve these purchases of XXXX cards. 
He then contacted the fraud department of Chase who said my son made these purchases so we are responsible for all the purchases. 
I was very frustrated and also called but got the same response. 
Two weeks later I decided to take it further so I called JP Morgan Corporate and asked to speak to Customer Complaints, I was promptly put through. 
I spoke to a youn woman who said the call maybe recorded, I hope it was. 
She listened to my complaint which really focused on, you called my husbands cell phone when you were aware of suspicious activity but when the very unusual activity continued you did not call again but emailed to his personal email 3 times. He did not open his personal email until he got home that evening but they never called back when XXXX was being spent on XXXX cards. Where was our protection. 
The youn lady listened and then said I need to bring another person into this call which she did. She was very professional and introduced us and the started to tell my the story. I interrupted because it was not exact so she the took herself out of the call and I continued with lady number XXXX. 
She listened and again I asked where was our protection. She then said, this was fraud and we will refund all of this money back to you. She said it would take a little time but to go ahead and pay the CC bill as usual I asked about finance charges and she said it will be refunded. 
At no time did she say this was under investigation or would it be. 
Two days later the money was back in our account. 
We received a letter from Chase a week later. 

This afternoon my husband received a call from Chase saying the money that was refunded to us was now going to be billed to our Chase CC because it was under investigation and they decided they were not covering these charges. He said it was in the letter that it was all under research. 

I do not remember the name of the lady I spoke to but if I heard it I would. I do hope the call was recorded. I am also not certain of the date but I believe it was XX/XX/XXXX. After our money was refunded I threw all my notes and scribbles away, I thought we were done. 

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