I usually start with this. Begin with niceties, and ramp up to lots of expletives!
You can add this form to the index.html in the public directory, or any other .html file in public so it is copied during build. Netlify will detect and process the form then. The data-netlify="true" goes on this form, not the main form in the component.
I’m a little confuzzled on your answer. So you’re saying I should create a 2nd form in the /public folder which has the bare minimum, while keeping the custom form i’ve created. Somehow this will work?
That will depend on whether everything else in your code is correct, which I suggest it isn’t. Have a look over the following article/tutorial (which is where my example is taken from, though implemented slightly differently)