用R语言的 alluvium包画桑基图时，想用target region数据来填充旁边的堆叠条颜色，代码报错，求帮助
是不是geom_stratum里的fill不能这么写，那应该怎么改正？

ggplot(as.data.frame(mydata_alluvia),aes(y=FDI.changes,axis1=Primary.sender,axis2=Target.state))+     geom_alluvium(aes(fill=Episodes),width=0)+   

geom_stratum(width=1/8,fill=factor(mydata$Target.region),color="grey")+   geom_text(stat="stratum",label.strata=TRUE,size=1.5,check_overlap = TRUE)+  

scale_x_discrete(limits=c("Primary sender","Target state"),expand=c(.05,.05))+   

scale_fill_brewer(type = "qual",palette="Set1")+     

ggtitle("Sanctions during 1970-2017")
Error: Aesthetics must be either length 1 or the same as the data (122): fill