R plot stat_function() by group, with parameters in df

Question

I did some non-linear regression and retrieved the fitting coefficients/parameters b0,b1,b2, and b3 in a data frame df. I would like to plot the same function with parameters from each row as an overlay with the initial data points (from df2) that I have used for fitting. All contained in one single graph. Any help is appreciated. Thank you in advance!

group	b0	b1	b2	b3
abc	6.3	8.9	1.66	0.025
def	5.1	8.9	1.48	1.27
ghi	5.5	9.0	1.41	1.03

group<-c("abc","def","ghi")
b0 <- c(6.3,5.1,5.5)
b1 <- c(8.9,8.9,9.0)
b2 <- c(1.66,1.48,1.41)
b3 <- c(0.025,1.27,1.03)
df <- data.frame(group,b0, b1, b2,b3)

I have tried to apply the solution from other posts but couldn't make it work.

The following just connects the points of all 3 functions without distinguishing between the group, as it does for geom_point() output

f <- function(x, b0,b1,b2,b3) b0*exp(-0.5*((x-b1)/b2)^2) + b3

ggplot(df2, aes(x = x, y = y, color=group))+ 
  geom_point() +
  stat_function(fun = f, args = list(b0 = df$b0, b1 = df$b1, b2 = df$b2, b3 = df$b3)) 

And the solution from here approach 2 returns

1: Computation failed in stat_function(): non-numeric argument to binary operator

coeflines <-
  alply(as.matrix(df), 1, function(df) {
    stat_function(fun=function(x){df[2]*exp(-0.5*((x-df[3])/df[4])^2) + df[5]}, colour="grey")
  })

ggplot(df2, aes(x=x, y=y, color=group)) +
  scale_x_continuous(limits=c(0,15)) +
  scale_y_continuous(limits=c(0,15)) +
  coeflines +
  geom_point()

Thank you for your help!