R语言Calibration曲线为啥只有一个点

是做的R语言nomgram校准取消，不知道为啥只有两个点，一个线

fit1 <- lrm(formula1, data = mydata, x=TRUE,y=TRUE)
cal1 <- calibrate(fit1, method = "boot", B=1000)

plot(cal1,
     xlim = c(0,1),
     xlab = "Predicted Probability",
     ylab = "Observed Probability",
     legend = FALSE,
     subtitles = FALSE)
abline(0,1,col = "black",lty = 2,lwd = 2)
lines(cal1[,c("predy","calibrated.orig")], type = "l",lwd = 2,col="red",pch =16)
lines(cal1[,c("predy","calibrated.corrected")], type = "l",lwd = 2,col="green",pch =16)
legend(0.55,0.35,
       c("Apparent","Ideal","Bias-corrected"),
       lty = c(2,1,1),
       lwd = c(2,1,1),
       col = c("black","red","green"),
       bty = "n") # "o"为加边框

能让我的图类似这样吗