InstallMedia (Books) and UserEnrollment

Hello,

what's the status of managing books with UserEnrollment context ?

I remember this used to work with a glitch : end user has to log in into Books with his/her managed Apple id (which could be problematic as you can't have both your books and organization books).

But I'm currently not able to make it work - A VPP user is associated (silent invite) to the right managed apple id, enough time (more than an hour) happened since a license has been associated to the VPP user and fetching the license from the API shows it has been set properly.

But installing the app via MDM always ends with error:

 <?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>Command</key>
	<dict>
		<key>MediaType</key>
		<string>Book</string>
		<key>RequestType</key>
		<string>InstallMedia</string>
		<key>iTunesStoreID</key>
		<integer>1525146196</integer>
	</dict>
	<key>CommandUUID</key>
	<string>e802d682-e8b1-6253-04f5-736dab7ecd13</string>
</dict>
</plist>

<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>CommandUUID</key>
	<string>e802d682-e8b1-6253-04f5-736dab7ecd13</string>
	<key>EnrollmentID</key>
	<string>971BB6F0-CA43-4B5E-9A1A-7BEF7A7BC286</string>
	<key>ErrorChain</key>
	<array>
		<dict>
			<key>ErrorCode</key>
			<integer>12047</integer>
			<key>ErrorDomain</key>
			<string>MDMErrorDomain</string>
			<key>LocalizedDescription</key>
			<string>A VPP purchase record for the item could not be found.</string>
			<key>USEnglishDescription</key>
			<string>A VPP purchase record for the item could not be found.</string>
		</dict>
		<dict>
			<key>ErrorCode</key>
			<integer>2615</integer>
			<key>ErrorDomain</key>
			<string>DeviceManagement.error</string>
			<key>LocalizedDescription</key>
			<string>Could not find Volume Purchase Programme assignment.</string>
		</dict>
	</array>
	<key>Status</key>
	<string>Error</string>
</dict>
</plist>```

Is this still a supported workflow ? Installing an App works without any issue in the same context.