Spam not moved to spam folder

Hi,

I've received a couple of mails recently which have the 'X-Spam-Flag: YES' in the header but are not being moved to spam. I am using the standard spam settings, with the exception of spam mails should be routed to 'junk' (I understand spam and junk folder are the same).

When i've spotted this, I've been logged into mail via IMAP (thunderbird on android). At first I thought the spam rules were only running when i logged in via webmail. However even when logged in via app.mailbox.org the mails did not move to SPAM. Any thoughts please?

Mail below - removed domain using redacted

Return-Path: <hello@boots.com>
Delivered-To: box+Junk@redacted
Received: from director-02.heinlein-hosting.de ([2001:67c:2050:104:0:1:25:1])
	(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits))
	by dobby44b.heinlein-hosting.de with LMTPS
	id CNBULRv6C2pbOwEAlp8NpQ:P1
	(envelope-from <hello@boots.com>)
	for <box+Junk@redacted>; Tue, 19 May 2026 07:50:19 +0200
Received: from mx1.mailbox.org ([2001:67c:2050:104:0:1:25:1])
	(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits))
	by director-02.heinlein-hosting.de with LMTPS
	id CNBULRv6C2pbOwEAlp8NpQ
	(envelope-from <hello@boots.com>)
	for <box+Junk@redacted>; Tue, 19 May 2026 07:50:19 +0200
X-Spam-Flag: YES
X-Spam-Score: 20.588
X-Spam-Level: ********************
X-Spam-Status: Yes, score=20.588 tagged_above=2 required=6
	tests=[ALL_TRUSTED=-1, HS_RSPAMD_40=20, HTML_FONT_LOW_CONTRAST=0.001,
	HTML_MESSAGE=0.001, MPART_ALT_DIFF=0.79, RDNS_NONE=0.793,
	SPF_FAIL=0.001, SPF_HELO_FAIL=0.001, URIBL_BLOCKED=0.001]
	autolearn=no autolearn_force=no
Received: from boots.com (unknown [51.143.153.205])
	by mx1.mailbox.org (Postfix) with ESMTP id F2EB92E054A
	for <box@redacted>; Tue, 19 May 2026 07:49:58 +0200 (CEST)
Authentication-Results: incoming_mbo;
	dkim=none;
	spf=fail (incoming_mbo: domain of hello@boots.com does not designate 51.143.153.205 as permitted sender) smtp.mailfrom=hello@boots.com;
	dmarc=fail reason="No valid SPF, No valid DKIM" header.from=boots.com (policy=quarantine)
From: boots <hello@boots.com>
To: box@redacted
Subject: 5/19/2026 6:49:58 a.m. =?UTF-8?B?U2hhcmUgWW91ciBGZWVkYmFjayAmIFJlY2VpdmUgYSBGcmVlIEdpZnQgZnJvbSBCb290cyAoQGJvb3RzVUspWW91ciBvcGluaW9uIG1hdHRlcnPigJRjbGFpbSB5b3VyIHRoYW5rLXlvdSBnaWZ0ISB8IEN1c3RvbWVyIHNhdGlzZmFjdGlvbiBzdXJ2ZXkgIEUtbWFpbDo=?=box@redacted NO:7099309-55685
Date: 19 May 2026 06:49:58 +0100
Message-ID: <20260519064958.40298459F9CFA858@boots.com>
MIME-Version: 1.0
Content-Type: multipart/alternative;
	boundary="----=_NextPart_000_0012_8DC57B50.F66842F8"
X-Rspamd-Queue-Id: F2EB92E054A
X-Rspamd-Score: 48.44 / 15.00 / 15.00
X-MBO-SPAM-Probability: **********
X-Spam: Yes