Buffers contain 2 default fields which are “_id” field and the “_dateUpdated” field.
If you don’t require these fields from your Buffer source step, you can delete the fields by adding a Calculator step after the Buffer source step. Type out the highlighted code in your Calculator step and click on Save to delete those fields as shown in the image below.
The below is the code to copy and paste in your Calculator step:
let inputRecord=input.record; delete inputRecord._id; delete inputRecord._dateUpdated; return inputRecord;