Contact Form 7 Selective Orange Border

Hey, I’ve been using contact form7 for almost a year on multiple website without a problem, but in the last month some people have been complaining that their submission are treated as SPAM (orange border) – I’ve disabled the CAPTCHA and it works for some people but still doesn’t for the others. Any thoughts? Success submissions came from multiple domains (gmail, yahoo) but as well as the failed ones.

Any help is appreciated, thanks!