M2M Field uneditable

Hi. I have 2 data models, and I added an M2M field in the first entity to link to the second entity. I encountered an issue when editing the first entity’s M2M field, where the interface for existing linked taggings is editable. Still, newly selected taggings will see a read-only interface when clicking into the linked entity. Is there any way to configure the linked entity to be editable when clicking the “Add Existing” option?