Verizon review: Formal complaint

To whom it may concern
I am writing to formally file a complaint regarding a deeply frustrating experience I recently had with Verizon customer service specifically concerning an unexplained issue to my account and the treatment that I received.
I have been a loyal Verizon customer for over 11 years during that time I have consistently paid my bill on time and have never had any major disputes. Recently it was discovered that I had been paying for a phone line that was fraudulent and that I never used. Verizon acknowledged this and issued $1000 credit to my account which I genuinely appreciated getting my money back.
At that time I had two active devices still under contract I asked a Verizon customer service representative if I could use part of the credit to pay off one of those devices in order to lower my monthly bill which was approximately $300 per month, I was told that that would not be a problem and to allow a few days for processing.
After waiting a week, I checked my account and found that not only had the device not been paid off but $500 had been removed from the credit and labeled as a buyout fee. I did not authorize any buyout and both devices remained active and unpaid.
I contacted customer service immediately to ask for clarification. Over the course of several hours, I was transferred to four different representatives each time I was assured that my issue would be resolved, and no one could explain why the $500 was deducted. I remained on hold for extended periods during each transfer, often close to an hour at a time.
Eventually after getting upset and tired of receiving the runaround from these representatives I requested a supervisor they again put me on hold for an hour where I was finally able to speak to a supervisor or a so-called supervisor. Because of the way that he treated me,I was not entirely convinced he was an actual supervisor there to help to resolve my problem. Sure enough I was right, this so-called supervisor placed me on hold for approximately another hour and ultimately told me and I quote exact wording” Verizon doesn't owe you nottin” This poor grammar response was continuously quoted to me every time I asked why the $500 had been taken out of my account.
Although the so-called supervisor continuously quoted” Verizon doesn't owe you nottin” At no point was I ever asking Verizon to “owe” me anything. I was asking for transparency and accountability regarding funds that were credited back to me because I had been wrongly charged for a fraudulent line.
This experience has left me extremely disappointed, the rudeness the disrespect the lack of empathy or even understanding left me disgusted. You need to do better.
Although this experience was extremely upsetting, I have remained with Verizon for over a decade because I believed in the company and trusted its service, however, the lack of explanation the dismissive treatment and the inability of any representative to provide clarity and respect along with the verbal abuse has seriously damaged my trust.
I am still under contract for my 2 devices and fully acknowledge my responsibility to pay them off however, I will be switching carriers once those obligations are fulfilled due to this experience. I would much prefer to resolve this matter properly as I am deeply concerned about the consequences from Verizon when I do leave, as they are already pressuring me to allow them direct access to my bank account to withdraw the money. I'm sorry but I was not born yesterday if they are already helping themselves to the credit that they gave me what would they do if they had full access to my account? That's just to give you an idea of how they've made me feel because customers should not feel that way especially if they are paying them monthly and are loyal. Their prices are way to overpriced to deal with this kind of treatment. There is something wrong with this company they need an overhaul, especially where customer service is concerned.

I am not seeking conflict I am seeking fairness and clarity $500 may not be significant to a big corporation but it is significant to me. I simply want accountability and respectful treatment as a long-standing customer.
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