Stack View breaks when switching to vertical axis - swift

Question

As a continuation of this problem. When I actually apply the constraints in a ViewController, I am finding that actually switching the axis to Vertical totally breaks the constraints.
Here is the before. It's looking proper.
Now here is after switching to vertical.
Totally baffled as to why this happens...
It says I need another width constraint, however the Stack View already has 2 width constraints:
Why is this happening and how can I fix this?
Here is my code:
<?xml version="1.0" encoding="UTF-8"?>
<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="18122" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="BYZ-38-t0r">
<device id="retina6_1" orientation="portrait" appearance="light"/>
<dependencies>
<plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="18093"/>
<capability name="Safe area layout guides" minToolsVersion="9.0"/>
<capability name="System colors in document resources" minToolsVersion="11.0"/>
<capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
</dependencies>
<scenes>
<!--View Controller-->
<scene sceneID="tne-QT-ifu">
<objects>
<viewController id="BYZ-38-t0r" customClass="ViewController" customModule="Test2Part" customModuleProvider="target" sceneMemberID="viewController">
<view key="view" contentMode="scaleToFill" ambiguous="YES" id="8bC-Xf-vdC">
<rect key="frame" x="0.0" y="0.0" width="414" height="896"/>
<autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
<subviews>
<stackView opaque="NO" contentMode="scaleToFill" ambiguous="YES" axis="vertical" spacing="7" translatesAutoresizingMaskIntoConstraints="NO" id="VP4-UJ-ETA">
<rect key="frame" x="0.0" y="424" width="0.0" height="48"/>
<subviews>
<label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="1000" verticalHuggingPriority="1000" text="asdlfkjlkjalskdjflakjsdlkfjalkjsdflkjasldkfjalkjsdflkj" textAlignment="natural" lineBreakMode="tailTruncation" numberOfLines="0" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" translatesAutoresizingMaskIntoConstraints="NO" id="Xej-eS-5Sd">
<rect key="frame" x="0.0" y="0.0" width="0.0" height="20.5"/>
<fontDescription key="fontDescription" type="boldSystem" pointSize="17"/>
<nil key="textColor"/>
<nil key="highlightedColor"/>
</label>
<label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" textAlignment="natural" lineBreakMode="tailTruncation" numberOfLines="0" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" translatesAutoresizingMaskIntoConstraints="NO" id="Xj4-8Q-inE">
<rect key="frame" x="0.0" y="27.5" width="0.0" height="20.5"/>
<string key="text">asldkfjalkjsdflkjasldkjfalkjsdflkjasldkjflakjsdlfkjalskdjflaqkjsdlfkjalksdjflaksdlfkjalskdjflakjsdlfkjalsdkjflakjsdflkjasldkjflakjsdflkjasdf</string>
<fontDescription key="fontDescription" type="system" pointSize="17"/>
<nil key="textColor"/>
<nil key="highlightedColor"/>
</label>
</subviews>
<constraints>
<constraint firstItem="Xj4-8Q-inE" firstAttribute="width" relation="greaterThanOrEqual" secondItem="Xej-eS-5Sd" secondAttribute="width" multiplier="1.2" id="xrh-Tq-uYT"/>
</constraints>
</stackView>
</subviews>
<viewLayoutGuide key="safeArea" id="6Tk-OE-BBY"/>
<color key="backgroundColor" systemColor="systemBackgroundColor"/>
<constraints>
<constraint firstItem="VP4-UJ-ETA" firstAttribute="centerY" secondItem="8bC-Xf-vdC" secondAttribute="centerY" id="ML4-KP-VmW"/>
<constraint firstItem="VP4-UJ-ETA" firstAttribute="centerX" secondItem="8bC-Xf-vdC" secondAttribute="centerX" id="ZUI-PV-Ofm"/>
<constraint firstItem="VP4-UJ-ETA" firstAttribute="width" secondItem="8bC-Xf-vdC" secondAttribute="width" id="aA4-hD-Jye"/>
</constraints>
</view>
</viewController>
<placeholder placeholderIdentifier="IBFirstResponder" id="dkx-z0-nzr" sceneMemberID="firstResponder"/>
</objects>
<point key="canvasLocation" x="26" y="89"/>
</scene>
</scenes>
<resources>
<systemColor name="systemBackgroundColor">
<color white="1" alpha="1" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
</systemColor>
</resources>
</document>