Repeating group won't change parent thing's type

Hi all,

I have started using a template to design my application. I am trying to take one of the repeating groups and change the displayed data type from one included within the template to my own data type.

as you can see in the above screenshot, I have changed the table’s data type to “stock items”. This is my data type and what i am hoping to display in the table.

however, when i try to edit text within the repeating group, all the dynamic data still refers to the old data type (which is tickets - deleted).

How can i change this repeating group so i can display my own data type?

I don’t know why this is not working as normally the data type changes instantly when i do this. I have checked all the parent groups that contain this element and none of them seem to have a data type set. What am i doing wrong?

There is no relevant option displayed in the dropdown - i don’t know what to select