Facing issue with Illustrator

I have been using my Adobe Illustrator regularly.. And since the past 1 week or so, I was making one portfolio in which it consists of 12 artboards... On saving and trying to convert to PDF, when the pdf is opening in chrome, it's showing me continuously, "This is an Adobe® Illustrator® File that was saved without PDF Content. To Place or open this le in other applications, it should be re-saved from Adobe Illustrator with the "Create PDF Compatible File" option turned on. This option is in the Illustrator Native Format Options dialog box, which appears when saving an Adobe Illustrator le using the Save As command" I have everything I could so in order to convert and print the exact Pdf, it's not helping me.... Please I know that you don't know me, I got you from Adobe community in chrome... Please help me and connect with me..