R package build check warning about "scales"

Question

I am building an R package, and I am constantly getting this warning about "scales" (below). I scanned my entire code, but I can't figure out where the problem is. Any suggestions would be helpful. Thanks!

> checking dependencies in R code ... WARNING
  '::' or ':::' import not declared from: ‘scales’

There are the packages that I am importing in my package.

Imports: 
    tibble,
    ggplot2,
    uwot,
    dplyr,
    tidyr,
    broom,
    tidyselect, 
    ggridges,
    Boruta,
    parallel
Suggests: 
    knitr,
    rmarkdown,
    testthat,
    covr