Has anyone added a combo box to a datasheet in a Access subform and found that row deletes are deleting from both the datasheet row source table and the combo box row source table?

Question

I have a Access front end and SQL back end that I just migrated to.

I have a form that provides a master ID to the subform to display the corresponding customer product details. The subform includes a combo box on each row to display the product name and allow you to change or add a record. If I delete a record in the datasheet the product record displayed in the combo box is also deleted.

How can I delete a record from the datasheet connected to one table without it also deleting the record from the combo box? I didn't have this issue with the Access DB backend. I've just migrated the backend to SQL and now this is happening. I've checked relationships and outside of connecting an ID from one table to the ID of another table nothing else is going on.

Has anyone added a combo box to a datasheet in a Access subform and found that row deletes are deleting from both the datasheet row source table and the combo box row source table?