Not gonna lie. I had this a lot when I worked in call centers. I always had customers that would call me an idiot or belittle me while always thinking they are in the right because “The customer is always right”. I would try to help them fix their problem or tell them we can’t do something because of a policy and if they didn’t like that they would argue with me about it the entire time saying other people have done it for them or other companies wouldn’t treat them that way. Which in my head I could only imagine myself getting onto them about it saying to go to that other company or I am sorry other agents went behind the company to break policy just for you but if it would shut you up I would consider breaking policy as well but I didn’t because I valued my job and stood for what I was trained on.
Just had to “kill them with kindness” the entire way through but believe me, it was draining every day of my life.