Some infopath fields are populating drop down list options in while editing in sharepoint library datasheet view while others aren't

Question

I have several drop down lists in a pretty simple Infopath form that I'd like to be able to edit in the datasheet view of their library on Sharepoint. After I publish the template form to the library, add new forms, and go to datasheet to edit, some of the fields retain their drop down lists while some don't - I'm assuming there's some simple step I'm missing on those fields that aren't keeping their drop down lists? Thanks in advance!