You've got a few choices.

If you log in and go to user settings, there's an option to get a private RSS feed. That has the names of the beers, your comments, and your photos. No ratings though.

It's possible to screenscrape the website.

You could try sending them a GDPR request for your data.

Finally, as I say in the post, you can pay to be an Untappd Insider - https://insiders.untappd.com/ - that will allow you to do an export of your data.