The problem The tidyverse api is one the easiest APIs in R to follow - thanks the concept of grammer based code. But every now and again you come across an error that boggles your mind, my personal one is the error spread delivers when I have no indexing for my data: Error: Duplicate identifiers for rows (2, 3), (1, 4, 5)…. I am sure we have all seen this some or other time.