93% of Kulula reviews are 1 or 2 star. Do you feel safe on their flights?

I had to cancel a booking because of a COVID travel ban. Kulula refused to refund my tickets. Instead, they told me they will create a Travelbank account and credit me with R2,989 (the amount of my tickets). On 30 December 2021 they issued the credit, but it expired immediately - on the same day, 30 December 2021. Obviously that was an error. It's now a month later. I've called 7 times, spent hours on the phone, emailed several times, all to no effect. Their response is "we are sending your query to our executive team for review". Seriously?! How difficult can it be to issue a new credit! It's bad enough that they made a mistake, but to not have fixed their own mess a month later seems really pathetic. Here's the thing. At the time of writing there are 2,900 reviews for Kulula and 93% of them are 1 or 2 star. They don't respond to any reviews. Clearly, Kulula is a badly run business, and apparently they don't care. So why would we think that the aircraft maintenance and flight operations are efficient and safe?