Y axis in R shows NA's in dot chart using gglot2

I have a data frame in R called df :

> df
# A tibble: 25 × 3
   delta cat    Year
   <dbl> <chr> <dbl>
 1  2.5  A      2019
 2  2    A      2024
 3  2.6  A      2020
 4  4    A      2022
 5  4.5  A      2023
 6  3    B      2019
 7  2.8  B      2024
 8  2.95 B      2023
 9  2.98 B      2022
10  3.07 B      2020
# ℹ 15 more rows

I have created a dot chart in R. using ggplot2 but in y axis that are the Years :

1. Are all of them NA
2. And are not sorted based on the evolution of the years (ie 2019,...2024)

YEARS <- c(2019,2020, 2022, 2023, 2024)
x=df%>%
  mutate_if(is.factor,as.character)%>%
  group_by(cat) %>%
  arrange(delta,.by_group = TRUE) %>%
  mutate(labels = paste0(letters[1:n()], "/",Year))%>%
  print(n=30)

x%>%
  mutate(Year = factor(Year, levels = rev(YEARS)))%>%
  group_by(Year)%>%
  arrange(Year)%>%
  ggplot(aes(x = delta, y =  Year
  )) +
  geom_point(size = 3) +
  geom_label_repel(aes(label = delta),                # Add text labels showing `delta`
                   size = 3,                         # Adjust text size
                   box.padding = 0.3,                # Padding around text box
                   point.padding = 0.2,              # Padding around points
                   segment.color = "gray",           # Line color
                   segment.size = 0.5) +   
  facet_grid(cat ~., scales="free_y") +
  scale_y_discrete(labels = \(x) str_extract(x, "(?<=/).*")) +
  labs(y =NULL) +
  geom_vline(xintercept=0) +
  theme_bw() +
  theme(legend.position = "none",                           # Remove the legend
        axis.text.x = element_text(angle = 0, hjust = 1),   # Rotate x-axis labels
        strip.text.y = element_text(size = 8, angle = 0, vjust = 0.5),
        axis.text.y  = element_text(size  = 7),
        strip.text = element_text(size = 14),               # Increase facet label size
        axis.title = element_text(size = 14),               # Increase axis title size
        axis.text = element_text(size = 10))+               # Increase axis text size
  theme(strip.background = element_rect(color="black", fill="gray", size=1.5, linetype="solid"))+
  labs(title = "",x = "")

how can I fix this ?

Data

df=structure(list(delta = c(2.5, 2, 2.6, 4, 4.5, 3, 
                        2.8, 2.95, 2.98, 3.07, 2.2, 3.3, 3.4, 3.9,5, 3.7, 2.9, 2.9, 
                        2.7, 2.9, 3.6, 2.3, 2.4, 2.3, 2.7), cat = c("A", "A", 
                                                                              "A", "A", "A", "B", "B", "B", "B", "B", "C", "C", "C", "C", "C", 
                                                                              "E","E","E","E","E", "D", "D", "D", "D", "D"), Year = c(2019, 
                                                                                                                                     2024, 2020, 2022, 2023, 2019, 2024, 2023, 2022, 2020, 2019, 2024, 
                                                                                                                                     2020, 2022, 2023, 2019, 2020, 2022, 2023, 2024, 2019, 2022, 2020, 
                                                                                                                                     2024, 2023)), row.names = c(NA, -25L), class = c("tbl_df", "tbl", 
                                                                                                                                                                                      "data.frame"))

Maybe I did not understand correctly the question but I tried to order the years on the y-axis inside each category relative to delta.

I hypothesized that there is no duplicate couple cat-Year in df. Then I just ordered relative to delta (no need to do it inside groups as if it is ordered globally, inside the group it is also ordered) and then creating a factor like your variable label with levels ordered as in the sorted df. Then with your code for plotting, the years are ordered relative to delta in each category.

df %>% 
  arrange(delta) %>% 
  mutate(yaxis = paste0(cat, "/", Year),
         yaxis = factor(yaxis, levels = yaxis)) %>% 
  ggplot(aes(x = delta, y =  yaxis)) +
  geom_point(size = 3) +
  geom_label_repel(aes(label = delta),                # Add text labels showing `delta`
                   size = 3,                         # Adjust text size
                   box.padding = 0.3,                # Padding around text box
                   point.padding = 0.2,              # Padding around points
                   segment.color = "gray",           # Line color
                   segment.size = 0.5) +   
  facet_grid(cat ~., scales="free_y") +
  scale_y_discrete(labels = \(x) str_extract(x, "(?<=/).*")) +
  labs(y =NULL) +
  geom_vline(xintercept=0) +
  theme_bw() +
  theme(legend.position = "none",                           # Remove the legend
        axis.text.x = element_text(angle = 0, hjust = 1),   # Rotate x-axis labels
        strip.text.y = element_text(size = 8, angle = 0, vjust = 0.5),
        axis.text.y  = element_text(size  = 7),
        strip.text = element_text(size = 14),               # Increase facet label size
        axis.title = element_text(size = 14),               # Increase axis title size
        axis.text = element_text(size = 10))+               # Increase axis text size
  theme(strip.background = element_rect(color="black", fill="gray", size=1.5, linetype="solid"))+
  labs(title = "",x = "")

I hope I understood the problem!