Email from Site Still Going to Gmail spam even with DKIM and header say that SPF has passed.

Hello,

I have my site set up to send users email when they do certain things (sign up for an account or ask to reset their password, etc). I noticed that those email were going to spam on server email address I tried. I used this article: https://www.digitalocean.com/community/tutorials/how-to-install-and-configure-dkim-with-postfix-on-debian-wheezy#add-the-public-key-to-the-domain’s-dns-records, to set up DKIM to try and fix this issue. Though, even after setting this up, when I try to send to a Gmail address the mail is still sent to spam.

One thing I have noticed though is that the headers say that Google is seeing the message as having passed the spf and dkim check that is done on incoming emails.

Here is what the headers look like:

Arc-Seal: i=1; a=rsa-sha256; t=1504230674; cv=none; d=google.com; s=arc-20160816; b=V5HeLxDwcsnKpAgYxZNb2y327zUFXqBVlOJVwUucE0p0ciiofBh8f4lzTRvXmRikEH RWp8pQN5c23PNbn9wpH2+URXZ3AztH//rWZimk9ZEdwtXIl2Xmee1bxlFtdwbQgmkGFa 7BlDnm6VsPfWSC+Q6ZQHttmQJkeAypv5Dl78EjoAvtRJHgKzTknUGJ2WDyqRtTO762/v nnu+szBELhFbjeT42O2GkGQNHL/Tf9lLrQb/9iE62p0bhS8OpLXuavf0ouwsANek+gPy Cje+UXLclo3qgyjLBcOkBdQRBdFaznbquQVKHmPgVgvg1JmmLjtdcCbt5UJU276G3hT6 ebUw==
X-Received: by 10.200.24.25 with SMTP id q25mr624414qtj.260.1504230674918; Thu, 31 Aug 2017 18:51:14 -0700 (PDT)
Return-Path: <www-data@mail.devplateau.com>
Arc-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@devplateau.com header.s=mail header.b=j/7ZTIv3; spf=pass (google.com: best guess record for domain of www-data@mail.devplateau.com designates 107.170.5.223 as permitted sender) smtp.mailfrom=www-data@mail.devplateau.com
X-Google-Smtp-Source: ADKCNb6Ay63iEYeS0Yo3Uiqm9SaoCqBuBUF/B5Ie5XGGh+Tzbc2etrVP2frHDn6CX6prRYLZ2fps
Mime-Version: 1.0
Authentication-Results: mx.google.com; dkim=pass header.i=@devplateau.com header.s=mail header.b=j/7ZTIv3; spf=pass (google.com: best guess record for domain of www-data@mail.devplateau.com designates 107.170.5.223 as permitted sender) smtp.mailfrom=www-data@mail.devplateau.com
Arc-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=date:message-id:mime-version:from:subject:to:dkim-signature :arc-authentication-results; bh=JG82wtXzhMJs79kwMbUAuICXbiXMjog4LfHm+AQTwLA=; b=QS47WSXmI9bc3H0B6TISGEoNyZiGOr5ACYhVkcI1paR29dr8XCG+cTgXkqMMzGx8Hj pudsbaV5xQy+IerEBT86E95mjmD4Ig/S44dInQ2AmpeixHF8VKdrpaSTYb+5XsrVNPC2 iWnMOjok7jhQE/BK9SDcIECnmC6+lF3wibW34OjFj/s17/3L1KePDV7+FRRFXAynEYbx PJ1ivsAuITPGAE7wiHc3pvdNfS4JEJLvz6NHc4yLzeVH5NF0yl0pY8wZyCrr6sKh6D/j 79OL04jP1gjuMmMgJn7rC5Yd7Yx+LftzENribPsy0K2ae+oodbj45yG1c5IKr8WiAByx 6Dog==
Dkim-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=devplateau.com; s=mail; t=1504230674; bh=JG82wtXzhMJs79kwMbUAuICXbiXMjog4LfHm+AQTwLA=; h=To:Subject:From:Date:From; b=j/7ZTIv33UfTIL7NGhFzd2yT5RZJL/0ngNhWI/vWZpK/vwP84/xNB/DOU3MscFetQ UvpSycvqsDMMK1iL75pPObU2Tt8BnRjlYM+6Sjk/4hia6vFfKc7A5Jj8HM+Ww3n6z3 u0NLsKlgWuuZAFSVXoiDfUhc29ohnjq77rIXI6Pk=
Message-Id: <20170901015114.04D72FFE51@devplateau.com>
Content-Type: text/html;charset=iso-8859-1
Received-Spf: pass (google.com: best guess record for domain of www-data@mail.devplateau.com designates 107.170.5.223 as permitted sender) client-ip=107.170.5.223;

Can anyone help me figure out why these mails are still being sent to spam? If you need more information, feel free to ask me for it.