Error connecting Through R

I am getting the following error when I paste the following code in the R script connector box. It is simple script that runs on RStudio.

df1 <- data_frame(school = c("A", "B", "C", "D", "E", "F", "G", "H"),
perc_25 = c(950, 1140, 1140, 820, 920, 950, 850, 850),
perc_75 = c(1190, 1410, 1380, 1030, 1130, 1150, 1060, 1050),
diff = as.numeric(perc_75 - perc_25))

Details: "ADO.NET: R script error.
Error: could not find function "data_frame"
Execution halted

Does nayone have any ideas why this not running. I have done some visual in powerBI using R previously but I am not sure what has changed. Thanks
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