There's a lot of context that's lacking here. What were the initial reviews like? If they were negative enough that everyone felt the paper couldn't be salvaged or there were major critical flaws, then probably no-one felt the need to waste any time looking at it twice. Or it could also be that your rebuttal did not address the critical issues pointed out by the reviewers. Or the reviewers plainly all sucked. If you'd be willing to link to the openreview page, it'd be easier to give you suggestions on what you should do next.