Hi @kanupriya,
If you would like to purge the recoverable items folder for a mailbox that is on hold, you need to first remove the hold from the mailbox, as the purpose of hold is to prevent emails from being permanently deleted from the mailbox.
Please refer to the steps in this Microsoft documentation:
Delete items in the Recoverable Items folder of cloud-based mailboxes on hold
You can re-enable the hold after the purge.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.