Hewlett Packard Enterprise

My printer broke under warranty. I called HP and they agreed to replace it. At one point the service was quite bad that I had to talk to a Supervisor. Now, a few weeks later I receive an email that they are going to charge me because I never returned the defective computer. I was on the phone with them for almost an entire hour, with the service associate and the Supervisor, and not a single time was there ever a mention of needing to return the printer. NOTHING. Not a mention, no return instructions mentioned or emailed, nothing. I thew out the printer the same day so I cannot return it. I explained this to them but their response via email is generic and says per our policy we can't refund. I did not authorize any charge to my credit card - this is deceptive business practices and fraud.