Creating map showing my data usingplotGoogleMaps

Question

I am trying to plot points on a map using R and plotGoogleMaps. I have a dataframe that I am attempting to use but I can not figure out how to do it.

My code is:

df <- data.frame(dbGetQuery(con, paste('select * from googlemaps')))

An example of the out to this is:

      T1141      LAT       LNG
1     A/BCD 51.48503 -0.062313
2     B/CDE 51.56495 -0.078709
3     C/DEF 51.54829 -0.0469517

The next code I use is this: coordinates(df) <- ~LAT+LNG

But this gives me the following error:

Error in .checkNumericCoerce2double(obj) : cannot retrieve coordinates from non-numeric elements

What am I doing wrong here?

EDIT:

I tried checking the mode of the column as suggested in the comment and this was the result:

coordinates(df) <- ~LAT+LNG Error in .checkNumericCoerce2double(obj) : cannot retrieve coordinates from non-numeric elements

mode(df$LAT) [1] "numeric"

mode(df$LNG) [1] "numeric"