Comparing two data frames with the same column and row names

I am trying to compare two data frames with the same column and row names but have different values. And select the columns with 20% change in values. I am trying to use compareDF package example here :https://www.r-bloggers.com/comparing-dataframes-in-r-using-comparedf/.

data_tls <- read.csv("tls_metrics.csv",header=T, na.strings=c("","NA","","NaN"))
data_uls <- read.csv("uls_metrics.csv",header=T, na.strings=c("","NA","","NaN"))

library(compareDF)
library(htmlTable)

compareData <- compare_df(data_tls, data_uls, c("Plot_name"))

compareData$comparison_df

print(compareData$html_output) 

However, the last row of code returns NULL.

Can someone please help?