Wrong identification of different type items as duplicate items

RamonMi

I have two items, one is a thesis and the other is a journal paper. Although their titles and authors (first author) are the same, as shown in the figure, items of different types can not be merged, and I don't think they should be automatically detected as duplicate items.

https://s3.amazonaws.com/zotero.org/images/forums/u7294073/5rlii54pza722qsickgj.jpg