"Error in parse - unexpected Symbol / {multcomp}"

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Hi folks

I'm trying to do a post-hoc test with the glht() function from the multcomp package. I receive an unexptected symbol error and I don't understand why.

Please find the example of the dataframe which should reproduce the error. It's my first question here and please forgive me if I didn't get the reprex perfect.

Many thanks in advance!

df1 <- data.frame(credit_amount = c(1169,5951,20960,78820,4870,9055,2835,6948,3059,5234),
                 job = as.factor(c("skilled","skilled",
                                   "unskilled resident","skilled","skilled",
                                   "unskilled resident","skilled",
                                   "high qualif/self emp/mgmt",
                                   "unskilled resident",
                                   "high qualif/self emp/mgmt"))
                 )


lm.credit <- lm(credit_amount ~ job, data = df1)  
  
library(multcomp)
  
  
ph.test.1 <- glht(model = lm.credit,
                    linfct = mcp(job = c("unskilled resident - skilled = 0")))
  
  
summary(ph.test.1)

Eliminate the blanks:

library(multcomp)
#> Loading required package: mvtnorm
#> Loading required package: survival
#> Loading required package: TH.data
#> Loading required package: MASS
#> 
#> Attaching package: 'TH.data'
#> The following object is masked from 'package:MASS':
#> 
#>     geyser

df1 <- data.frame(
  credit_amount = c(1169, 5951, 20960, 78820, 4870, 9055, 2835, 6948, 3059, 5234),
  job = as.factor(c(
    "skilled", "skilled",
    "unskilled_resident", "skilled", "skilled",
    "unskilled_resident", "skilled",
    "high qualif/self emp/mgmt",
    "unskilled resident",
    "high qualif/self emp/mgmt"
  ))
)


lm.credit <- lm(credit_amount ~ job, data = df1)



ph.test.1 <- glht(
  model = lm.credit,
  linfct = mcp(job = c("unskilled_resident - skilled = 0"))
)


summary(ph.test.1)
#> 
#>   Simultaneous Tests for General Linear Hypotheses
#> 
#> Multiple Comparisons of Means: User-defined Contrasts
#> 
#> 
#> Fit: lm(formula = credit_amount ~ job, data = df1)
#> 
#> Linear Hypotheses:
#>                                   Estimate Std. Error t value Pr(>|t|)
#> unskilled_resident - skilled == 0    -3722      23165  -0.161    0.878
#> (Adjusted p values reported -- single-step method)

Created on 2021-01-03 by the reprex package (v0.3.0.9001)