Anyone knows good plagiarism checker for content writing??

Question

I wrote content inspired from 1 websites before submitting the content I checked on free versions of copy scape.com and smallseotools.com, it showed 100% unique but
Unfortunately, when I submit the article I got reply from the company.. that.. it didn't pass plagiarism check.. I can't ask them which tool they are using.. but they showed me the result.. my content was similar to 3 website which I don't know.. I didn't use them as a source to collect information...

Answer 1

You can just simply don't plagiarize. Rephrase the words and sentences from the original author. And then give credit