error running observed data plot with predictions

[mshaer-pkpd]

Tried to run this code:

dataEx$plot(line = list(join = FALSE, pred = NPex$post), xlim = c(119,146))

but got this error:

! Can't join x$id with y$id due to incompatible types. ℹ x$id is a . ℹ y$id is a .

[Siel]