Where can I complain about the consumer service?

I just got in touch with customer service senior advisor after having a long text consultation regarding the signal problem of my iPhone. I'm not an American, so I'm not good at explaining in English, but I did my best. But she listened to my speech, and she sarcastically said what I was saying, ignored what I was saying, and repeatedly said it. When I asked her to hand my. case over because I wanted to talk to another senior manager, she started mocking me. I've never had this kind of experience talking to Apple before. If anyone knows, could you tell me the email or contact information that I can leave an official complaint with? I asked them in text, but they only tell me the product feedback webpage.