If you want to issue the hold to the custodian who is in Unpublished status in the legal hold and send the hold notice to the custodian please follow the below steps.

Open the respective legal hold--> CUSTODIANS/NCDS -->Select the checkbox of the respective custodian who is in Unpublished status --> click on Issue.

By performing the above mentioned action, the custodian's status will be changed to Issued, and the custodian will receive the hold notice and the Interview (if any). I have added the reference screen shot below to show how the custodian legal hold status will be on performing the above-mentioned action.