It has now gone live:
After endless conversations with my Success Manager, thousands of comments from confused sellers here in the forum and the hope that the wrongfully negative Order Cancellations would be deleted and thus no longer affect me ... all of this has achieved nothing.
I am now officially a level 0 seller on page 1 of best-selling gigs (let's see for how long) thanks to negatively affecting order cancellations (1 out of 545 orders was cancelled), an average 5-star rating, Repeat Buyer's Badge and high-quality customers like Google, Renault, Volkswagen, and co.
That doesn't feel good, it's a shame that no help can be expected.
By the way: My Success Manager recently said that the order cancellations that have a negative impact on the Success Score, even though they were caused by Customer Support and should never have affected us, were NOT a bug. It was intended that they would affect us, but Fiverr has changed its mind (even though that wasn't helpul at all, at least yet).
Anyway, have a nice evening, I hope you're doing better.