I’m sorry to hear about your experience - I’ve heard many similar experiences from others before, mainly coming from freelancing platforms (although that doesn’t mean the platform is the problem - it’s the people, haha!)
Maybe you should tighten up your vetting process? Don’t believe everything you see in testimonials - some people actually buy testimonials! Do look at the negative reviews, if any, maybe they shed some more light or trigger some flags (although the bad reviews can be bought just as well - this is getting tiring to think about!)
And you can even engage in a conversation with a potential freelancer, ask some basic questions, see how they reply, what their writing style looks like…
What did you buy?
Can I take a wild guess whatever you bought was from Fiverr?
Just saying because you mention you buy a lot of stuff there.