>>156342
Three questions:
How common is your name where you live?
What did you do?
Where did you post this?

If someone finds a page with your name on it, you can say that it's someone else/a bot/an account your relatives made, that got hacked later on and started posting spam.

If you posted pics or a video then that's something else. How bad is it? Like "I play pokemon go song" levels of bad, or 14/88 levels of bad? Or is it "devious lick" activity level of bad?

Finally, see if you can delete the file and account on the website. An old saying is that "everything you post on the internet is forever", but link rot, site restructuring and unpaid hosting has claimed many files I've been looking for; these only remain in the local disk stores of people who saved them. If you're lucky, the website you posted to will be inaccessible in the near future. Of course, if what you did is absolutely ridiculous, it's a certainty that someone has archived it or reuploaded it. Though whether anyone knows the right person to contact to get the file is up to chance.

Ultimately, do not underestimate the power of obsessively dedicated witch hunters on the internet, especially if they're on a moral crusade. I don't have any advice on stopping them, sorry I can't be of more help OP.