mail ends in google spam folder while SPF pass, DKIM pass, DMARC pass

Question

I am trying to send basic mail to a gmail user test and the mail ends up in the spam folder. I don't really understand why. I used to send through ubuntu sendmail, spent a lot of time setting up postfix/dovecot but it still ends in spam. And the same with outlook/live !

I have looked at other posts but don't see how to solve it.

using Mxtoolbox, I don't see a problem : https://mxtoolbox.com/domain/gerant-immo.com/

headers seems ok too :

ID du message    
Date de création :  27 février 2018 à 16:54 (Temps d'envoi : 0 seconde)
De :    Pierre Mouilhade Message envoyé avec mail (GNU Mailutils 2.99.99)
À : test.gerantimmo@gmail.com
Objet : testing
SPF :   PASS avec IP 54.37.157.157 En savoir plus
DKIM :  'PASS' avec le domaine gerant-immo.com En savoir plus
DMARC : 'PASS' En savoir plus

Delivered-To: test.gerantimmo@gmail.com
Received: by 10.25.142.149 with SMTP id a21csp5148448lfl;
        Tue, 27 Feb 2018 07:54:26 -0800 (PST)
X-Google-Smtp-Source: AH8x225LRChHqPMrsmVBeMzyZ80JcAFNz3ZGdA/iXknZaKJG85qi/B5PgdSHEzHjT1X/51LQc1bQ
X-Received: by 10.223.182.156 with SMTP id j28mr12863054wre.66.1519746866884;
        Tue, 27 Feb 2018 07:54:26 -0800 (PST)
ARC-Seal: i=1; a=rsa-sha256; t=1519746866; cv=none;
        d=google.com; s=arc-20160816;
        b=uyqDpNd/HSwglqKIzQ34pCAv38Ns0M43dzzFuLhwBz3ImRSGZdxXEH6RaDe9TDKW5L
         /e1K2Ih51KLjH43z2Dker5tmOzSlqSNIFnnFens3b8STr/1r0dnrjKhb0fgmbYYq8Zl3
         TJDa/CcwcBEp/kgfqP52fb/TxX2we1dEOEQLckBxvg4ihDg8gJ4ixf55Byi/QqKtnOrB
         NXrqCY0axq6qlcBQ1vDDbdKgrSTdpWctiMlcJN+IAWGOX8wBYxcw2r9oPlWq5p60h0T3
         vB9o2Fe1INVCZ7GvKPaUcQvhBs6mqH4HLeo7Zg+F9KE+K6ls+i8vyhamUCiw+/mgzZX3
         +B5g==
ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816;
        h=from:date:message-id:subject:to:dkim-signature
         :arc-authentication-results;
        bh=nypZpg5l+81aPhtySK35KJDOOjKxnkP7R1HCZXGW3hM=;
        b=I2vwwSB4v0pK6Daa9NsWW7fC222N0hes9UVPHygu1GqtAjIlSaxUqzET158CsuKJQE
         gmKbRA1cQFYXpb6Kq0RhupMNzuaERiiEPWOWNwjh1SsSltCPkZGlotr6VwZjN9C9xN/k
         3O5bxBDZ+CiTVKutAU9RvDji50nWle1kSrb1D7+r/s5OJtJ6tlpAWtWCU9TZvui98sHB
         +o5gaUiCDzPszL9yOJ8tlm6EAlypTmqkAwN15RTk/A4qKO85DYgbQsW/N5j2GAsCPb6E
         yhBO+9tnEQL276GH+maPmAoFr+L3h6eUCflWQTYDVCXt1MuCZXj+jGeVfOKfJRiBNTsy
         OkHg==
ARC-Authentication-Results: i=1; mx.google.com;
       dkim=pass header.i=@gerant-immo.com header.s=mail header.b=je4Cox0q;
       spf=pass (google.com: domain of pierrem@gerant-immo.com designates 54.37.157.157 as permitted sender) smtp.mailfrom=pierrem@gerant-immo.com;
       dmarc=pass (p=REJECT sp=NONE dis=NONE) header.from=gerant-immo.com
Return-Path: 
Received: from gerant-immo.com (gerant-immo.com. [54.37.157.157])
        by mx.google.com with ESMTPS id m2si877353wmh.123.2018.02.27.07.54.26
        for 
        (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128);
        Tue, 27 Feb 2018 07:54:26 -0800 (PST)
Received-SPF: pass (google.com: domain of pierrem@gerant-immo.com designates 54.37.157.157 as permitted sender) client-ip=54.37.157.157;
Authentication-Results: mx.google.com;
       dkim=pass header.i=@gerant-immo.com header.s=mail header.b=je4Cox0q;
       spf=pass (google.com: domain of pierrem@gerant-immo.com designates 54.37.157.157 as permitted sender) smtp.mailfrom=pierrem@gerant-immo.com;
       dmarc=pass (p=REJECT sp=NONE dis=NONE) header.from=gerant-immo.com
Received: by gerant-immo.com (Postfix, from userid 1002) id 7FCE4839C6; Tue, 27 Feb 2018 16:54:26 +0100 (CET)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gerant-immo.com; s=mail; t=1519746866; bh=nypZpg5l+81aPhtySK35KJDOOjKxnkP7R1HCZXGW3hM=; h=To:Subject:Date:From; b=je4Cox0qlmTJAP6tatdYK8WyrvLALo3kjnjADH+zXsFy+Wp2ZS5yaj4/srqWe6dFT
     JChGxIJ7SUR6ytEJiadKwhkw35/FOimVj1lNSLKa/cP8ljpI7dn9l6WDDx2vdL/kqj
     1XSvi31gk2Cmi9nYCx+EYbxSHembKIQ/K0pRjfes=
To: