Your gig description looks fine and samples too, but the review raises a question.
So another opera singer like yourself from US hired you to do VO work for them?
I’m not jumping into conclusions here, but it looks odd to be honest.
For a savvy buyer that would be a red flag. There’s nothing wrong with outsourcing, but try to get a few more reviews.
I hope Fiverr is not the only platform where you provide you service. So I would recommend reaching out to your clients off Fiverr and ask them to process some orders through Fiverr.