 # Regressionsanalyse - NA as coefficients

Hey i have a problem with my regression analysis
I have 4 Treatment Groups, thus I've tried to build Dummy Variables for those. Then I wanted to put those dummies in the Regression as dependent Variables. I used the Trigger of my Survey to build those new Variables by recoding them ...

The problem is that I only get NA's as coefficients, which is super frustrating cause I don't find the problem

# Treatement 1

Rohdaten_xlsx\$DT1 <- recode(Rohdaten_xlsx\$c_0001,"1=1;2:4=0")
Rohdaten_xlsx\$DT1

#Treatment 2
Rohdaten_xlsx\$DT2 <- recode(Rohdaten_xlsx\$c_0001,"2=1;1=0; 3:4=0")
Rohdaten_xlsx\$DT2

#Treatement 3
Rohdaten_xlsx\$DT3 <- recode(Rohdaten_xlsx\$c_0001,"3=1;1:2=0;4=0")
Rohdaten_xlsx\$DT3

#Treatement 4
Rohdaten_xlsx\$DT4 <- recode(Rohdaten_xlsx\$c_0001,"4=1;1:3=0")
Rohdaten_xlsx\$DT4

#Regression mit Dummies --> Problem nur NA Werte
Model_Preise_2<- lm(Rohdaten_xlsx\$KB_T1~ Rohdaten_xlsx\$DHP1n+ Rohdaten_xlsx\$DHG1n +Rohdaten_xlsx\$DT1+ Rohdaten_xlsx\$DT2+Rohdaten_xlsx\$DT3)
summary(Model_Preise)

My professor said I Also can use as.factor in my regression, because this would build the dummies
-> I just don't know how to use these