Error on Data Mapper Post Action in Omniscript

Hi all, 

I'm getting an error message, when previewing my omniscript - specifically on the data mapper post action: "Required fields are missing: [Name]". 

 I am trying to update a custom field on the Quote object. When previewing it in the data mapper itself, it updates the records fine. However when previewing in omniscript it throws an error. Does anyone have any insights into this? 

NOTE - Omniscript is sample "Single Doc Core - DOCX Serverside(LWC)" with few additional steps.