Remove gray/grey shadow from Leaflet map in R

General
1

Folks, I have a problem. My map has an unusual gray shadow. I use shapefiles

countries <- readOGR(".","ne_50m_admin_0_countries")

or geojson

url <- "https://raw.githubusercontent.com/datasets/geo-countries/master/data/countries.geojson"
countries <- geojson_read(url, what = "sp")

Does not matter, both have the same error.

enter image description here

I had this issue before but did not find a sustainable solution and my search did not help, that is why I am here.

How do I color?

# Color palette
colorFactors = colorFactor(c('red', 'orange', 'blue', 'green'),
                      domain = dfs_pg$Region)

# Create a map
leaflet(dfs_pg) %>%
addProviderTiles(providers$OpenStreetMap) %>%
addPolygons(stroke = FALSE, 
          fillOpacity = 0.75, 
          color = colorFactors(dfs_pg$Region), weight = 1)

There are multiple NAs and I tried to omit them - did not work for me. I want to keep NAs the same color as the original provider without this shadow.

I merge my csv and geojson into a spatial dataframe.

The same problem is for ANY provider.

Really appreciate your help! Thanks!