The real problem here is you set your nameservers to ns1.heliohost.com and ns2.heliohost.com. That's not our domain. You said it right in your forum post, but set it wrong on freenom's website.
The funny thing about this is if it's a good robot it will obey this rule and not crawl your site. If it's a "bad" robot, which is what OP is trying to block, it will ignore the rules and crawl anyways.