Copy the video below inside the BP_MasterHoldable blueprint.

Add the highlighted nodes shown in the image below, location at the top of the image.

Untick the Start with Tick Enabled in the BP_MasterHoldable Class Defaults like shown in the image below.

You can also disable tick in the BP_MasterAttachment blueprint like shown in the image below, keep in mind if you add attachments in the future that need to tick you will need to enable this in their attachment blueprint.