Week day error when using timeVariation function in R

Question

I am using library openair in R to create a timeVariation plot that should look like the image.

Anyway I am getting the following error and I don't know why it appears

Error in `mutate()`: ℹ In argument: `wkday = wday(date, label = TRUE, abbr = FALSE)`. Caused by error in `factor()`: ! invalid 'labels'; length 6 should be 1 or 7

I tried with some openair data and it remains. The code for that example is:

library(openair)
mary <- importAURN(site = "my1", year = 2000)

timeVariation(mary, 
              pollutant = 'no2',
              type = 'month')

Does anyone know why is it happening? Thanks in advance.