Product: Checking or savings account

My XXXX year old XXXX XXXX mother added me to her account several years ago. She was very ill at the time and wanted me to be able to make transactions on her behalf should she be too ill to do so. We explained this to the bank staff who actually added me. We actually asked what was the best way to go about doing this and was told that it would be to add me to the account. Years have gone by and I have never benefited from any of the funds in the account. I have never added any of my own money to the account. 
My husband and I had an account with Huntington as well. Apparently, it had been charged off. We had NO knowledge of this. In fact, we opened a second account a few years later and was never told by anyone that we owed any money. Unfortunately, my husband lost his job and this second account was charged off as well. This happened long enough ago that I had forgotten about it. 
On Wednesday XX/XX/2018 my mother had funds withdrawn from her retirement account and deposited into her checking account. 
On Friday XX/XX/2018 Huntington withdrew a sum of XXXX and a sum of XXXX for a total sum of XXXX On Monday XX/XX/2018 My mother phoned Huntington Bank customer service. She was told that because I was co signer on the account that they had a legal right to withdraw these funds. She insisted that I had only been on the account to assist her. None of the funds in that account were mine. The person who she spoke with was rude and refused to do anything. 
I also phoned Huntington customer service on Monday XX/XX/2018. I adamantly stated that I was not aware of the debt. That I had not been contacted in regard to the debt. Also, this is a shared debt with my husband. I do not understand why I was being held solely responsible. I pointed out that even if this was a debt that I had with them I would dispute the debt if given the chance. Finally, how could I have known about the first amount if they allowed us to open another account with them? I begged the person I spoke with to take the information back to their legal team and at least have the issue evaluated again. I was told that the accounts are reviewed very carefully before they take money out. The bank staff refused to even try to get the legal team to take a second look. 
Once again on Monday XX/XX/2018 my mother again called Huntington Banks customer service. She wanted to know why they would take these funds without notifying her. They stated that they did not have to notify her. They reasserted that because my name was on the account that they had every legal right to take the money. Huntington is very aware that the funds came from a retirement account that my mother can not withdraw from again this year without suffering huge penalties. In the end, she requested that a manager or supervisor call her. 
On Tuesday XX/XX/2018 She received a call from someone named XXXX XXXX. She asked if she was a supervisor and XXXX XXXX responded by telling my mother that she was office staff but that was as high up as my mother would be ALLOWED access to. XXXX  XXXX insisted with a very nasty attitude that what Huntington did was right. That my mother could do absolutely nothing about it to have it reversed.

Our research indicates that this account meets every guideline for being a convenience account. Huntington has stated that they do not offer these accounts. Still, since I did not benefit from any of these funds, my name was only later added to the account, and the funds in question clearly came from the retirement account owned solely by my mother. Finally, even if in the end they had a right to take the money, why didn't they take half and hold my husband responsible for the other half? This could and should have been worked out differently. I have repeatedly requested more information in regard to the debt ( s ) that Huntington claims the funds were taken for. I was told they only have the amounts owed and no other information. I was not even given the chance to dispute these debts.