Deleted Items folder in archive

Hello Iniobong,

Thank you for posting your question in this community.

There are few things that you should check in this kind of situation:

1. Is retention policy assigned to the mailbox?
2. Is there any hold on the mailbox that prevents deletion?
3. Is the mailbox under eDiscovery investigation?

Posible resolutions

• Check if there is any hold on the mailbox, kindly refer to this Microsoft documentation for guide:
  https://learn.microsoft.com/en-us/purview/ediscovery-identify-a-hold-on-an-exchange-online-mailbox
• You can generate hold report to have more insight on it. Refer here: https://learn.microsoft.com/en-us/purview/ediscovery-hold-report
• If it occurs that the mailbox is under hold based on the result of previous step, follow the instructions in this Microsoft link to remove the hold and delete the emails
  https://learn.microsoft.com/en-us/purview/ediscovery-delete-items-in-the-recoverable-items-folder-of-mailboxes-on-hold

NOTE: it might be critical and consequential to delete messages from a mailbox under eDiscovery. Before proceeding with removing holds and deleting the emails, ensure that you have the right authorization to do so.

Do well to let me know if this helps.

Thank you.