如何修复错误消息以在R中绘制线图？

我试图根据上半正态模型（hn.l.s）中的估计值，绘制出真实尺度上的密度与协变量之间的直线图。如何消除这两条错误信息并绘制线图

dist <- seq(0, 60, 15)
obs <- as.matrix(dat[, 1:4])
site_covs <- data.frame(shrub = dat[, c("d.shrub")], light=dat[, c("light")])
umf<-unmarkedFrameDS(y = obs, siteCovs = site_covs, dist.breaks = c(dist), 
                     survey = "point", unitsIn = "m")
hn.l.s <- distsamp(~light~shrub, umf, keyfun = "halfnorm", output = "density", 
                   unitsOut = "ha")
pred.hn.l.s <- predict(hn.l.s, "state", se.fit = TRUE)
backTransform(hn.l.s, type = "state") 

xy.coords（x，y，xlabel，ylabel，log）中出错：

“x”和“y”长度不同

plot(hn.l.s, pred.hn.l.s, type = "l", ylim = c(0,60), xlab = "Distance", 
     ylab = "Detection probability")