R (ggplot2): Add spacing between bars position_dodge() does not work

Question

I am trying to generate barplots with ggplot2 and want to decrease the spacing between the bars. I already decreased the bars width but now there is lots of space between the bars. Can I move the bars closer together or decrease the plots width somehow?

I found multiple people saying it's possible with position=position_dodge(width=__) as an argument in geom_bar(). For some reason, adding this and changing the number does not change anything about the plot, no error code either. This is my code for the barplot:

ggplot(t.summary, aes(Stamm, Intensitaet)) +
  geom_bar(aes(fill = Stamm),
           position=position_dodge(width=1),  #does not work
           show.legend = FALSE,
           stat="identity",
           alpha=0.8,
           width=0.3,
           color="black") +
#I added significance stars 
  geom_signif(data = t, comparisons = list(c("hul5d", "Hul5")),
              y_position = 570, tip_length = 0.04, vjust = -0.1,
              map_signif_level = TRUE) +
  geom_signif(data = t, comparisons = list(c("Hul5_C878A", "Hul5")),
              y_position = 200, tip_length = 0.04, vjust = -0.1,
              map_signif_level = TRUE) +
  geom_signif(data = t, comparisons = list(c("Hul5_C878A", "hul5d")),
              y_position = 515, tip_length = 0.04, vjust = -0.1,
              map_signif_level = TRUE) +
  labs(x="Strains", y="Intensity compared to WT [%]") +
  geom_errorbar(aes(x=Stamm, ymin=Intensitaet-sd, ymax=Intensitaet+sd),
                width=0.1,
                colour="black",
                alpha=0.9,
                size=0.5)+
  scale_fill_brewer(palette = "Blues") +
  theme_bw(base_size=18) +
  theme(panel.grid.major = element_blank(),
        panel.grid.minor = element_blank())

I figured everything else out but cannot seem to get this. Help is very appreciated!!