Walk away. Review the feedback. And, solve the problem. A few keys to maintaining editing boundaries with clients.
Some editors have waiting lists full of projects. How do they get the deadlines to move? For some, they have “clients” who prefer them. Secondly, they ask.
No matter how a prospective client finds you it’s your responsibility to make sure you’re a good match.
When a client pays a fixed price for a project, rather than an hourly rate, it’s important for freelance editors to use their time wisely.
In all seriousness, there are as many legitimate paths to a good grounding in the fundamentals.