Bare metal recovery backup using 'Windows Server Backup' keep failing

I have a VM of Windows Server Essentials 2019 as a AD/DC, hosted using Hyper-V Core. I am trying to carry out a 'Bare metal recovery' backup but the job keeps failing, the log below seems to suggest a permissions issue either the Recovery or EFI System partition, any assistance would be much appreciated!

Log Name:     Application
Source:       SRMSVC
Date:         02/07/2019 08:07:12
Event ID:     8228
Task Category: None
Level:       Error
Keywords:     Classic
User:         N/A
Computer:     DC-01.giarti.local
Description:
File Server Resource Manager was unable to access the following file or volume: '\\?\Volume{b5dd8a31-0f5d-4997-923d-36641d2310aa}\'. This file or volume might be locked by another application right now, or you might need to give Local System access to it.
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">;
  <System>
    <Provider Name="SRMSVC" />
    <EventID Qualifiers="32772">8228</EventID>
    <Level>2</Level>
    <Task>0</Task>
    <Keywords>0x80000000000000</Keywords>
    <TimeCreated SystemTime="2019-07-02T07:07:12.059045100Z" />
    <EventRecordID>2335</EventRecordID>
    <Channel>Application</Channel>
    <Computer>DC-01.giarti.local</Computer>
    <Security />
  </System>
  <EventData>
    <Data>\\?\Volume{b5dd8a31-0f5d-4997-923d-36641d2310aa}\</Data>
    <Data>
    </Data>
    <Binary>2D20436F64653A2053524D564F4C4D4330303030303730392D2043616C6C3A2053524D564F4C4D4330303030303636392D205049443A202030303030313933322D205449443A202030303030343338302D20434D443A2020433A5C57696E646F77735C73797374656D33325C737663686F73742E657865202D6B2073726D737663732020202020202D20557365723A204E616D653A204E5420415554484F524954595C53595354454D2C205349443A532D312D352D313820</Binary>
  </EventData>
</Event>


Kind regards

Trevor