This was at a company that generally treated me alright and was staffed with generally reasonable people, so I can't imagine the Kafkaesque nightmare that it must be to work at a notoriously chaotic, evil company like Uber, especially as a woman (which I am not).
The lesson, as so many other people in this thread have already said, is that HR is not looking out for you. Keep your own counsel and get everything in writing, and prepare for their attempts to bully and gaslight you into a marginalized position.