I think you can make midjourney stop by using social media pressure, but you need to improve communications. For example don't start with "I'm making 16k a month" because most will think you can afford a lawyer.

Also, I repeat, consider explaining better what you do and what exactly are they accusing you of doing wrong and why they are wrong in doing so.

Also now that I see the screenshots, the way you phrased things it did look like you were the official midjourney api, so the trademark violation is there for sure.