今天在使用ggplot2绘图的时候遇到了了如图所示的问题,请问有没有人可以帮忙解答一下=m=

```r
library(Rmisc)
library(reshape2)
library(ggplot2)
library(readxl)
df1= read_excel("C:/Users/chenp/Desktop/aus.xlsx")
df2= read_excel("C:/Users/chenp/Desktop/aus2.xlsx")
data1 <- melt(df1,id='WEEK',measure=c("AH1","AH1N12009","AH3","AH5","ANOTSUBTYPED","BVIC","BYAM","BNOTDETERMINED"))
data1
value <- data1[,c(3)]
data1[,c(3)] <- as.numeric(unlist(data1[,c(3)]))
p = ggplot(data1, aes(x=WEEK,y=value,fill=variable))+
geom_bar(position="stack",stat="identity",width=0.9)+
geom_text(aes(label=value,y=value+400))
colnames(data1)[seq(2,ncol(data1), 15)]
rownames(data1)[seq(2,nrow(data1), 15)]
p
p+theme(
text = element_text(size=10),
axis.text.x =element_text(angle=90, vjust = 0.5),
panel.background = element_blank(),
panel.grid =element_blank(),
)+
theme(axis.line = element_line(size=0.5, colour = "black"))
```