A few days ago I deleted all of my posts and comments from reddit, but today they somehow reappeared.
I don’t know if that’s a bug or the admins themselves are restoring content, but I’m sure they’d have incentives to do so considering that they make money from your content, whether that is from generated clicks to the website or from selling those data to other companies to train AI models.
FYI: if the issue is using a bot to delete as some speculate, you can sort your comments by top and delete those manually. Those are highest visibility.