Why is my single line being split into multiple lines. This is also causing inaccuracies and my lines to not be parallel

Why isn’t this just a single line? Why did it split it up for no reason?

foobar2

Turn on hidden geometry and you will probably see hidden edges.

Best of all, download the model to your computer and drag it into a reply here so we can check it for you.
Looks like you have some clipping going on too.