The following code is returning the error of the title. The strange thing is that I am running the same code for other tables (those other tables has the same variables) and everything is ok.
p14 < is_1970_2 %>%
ggplot() +
geom_line(aes(year, f_rel_is, colour = countryname)) +
geom_smooth(aes(year, f_rel_is, color=d_man)) +
gghighlight(max(f_rel_is)>0) + labs(subtitle = "Normal deindustrialization", y="Is Factor", x="Year") + coord_cartesian(ylim=c(3,10))
p14 < is_1970_2 %>%
 ggplot() +
 geom_line(aes(year, f_rel_is, colour = countryname)) +
 geom_smooth(aes(year, f_rel_is, color=d_man)) +
 gghighlight(max(f_rel_is)>0) + labs(subtitle = "Normal deindustrialization", y="Is Factor",

x="Year") + coord_cartesian(ylim=c(3,10))
label_key: countryname
p14
geom_smooth()
using method = 'loess' and formula 'y ~ x'
geom_smooth()
using method = 'loess' and formula 'y ~ x'
Erro: Continuous value supplied to discrete scale
geom_smooth()
using method = 'loess' and formula 'y ~ x'
geom_smooth()
using method = 'loess' and formula 'y ~ x'
Error: Continuous value supplied to discrete scale