[R] Error when running a basic joint model

[Isaac Singini]

Dear All
I have the following two datasets for joint modeling the survival and longitudinal data. However when I run the joint model I get the following error. I am new to R, may someone assist

Error in `[.data.frame`(lmeObject$data, all.vars(TermsX)) :  undefined columns selected

Data structure  for the longitudinal analysis is: 
str(cd4long)
'data.frame':	464 obs. of  6 variables:
 $ id1       : int  1011555 1011555 1011555 1011555 1011558 1011558 1011558 1011558 1011568 1011568 ...
 $ week      : int  2 4 6 12 2 4 6 12 2 4 ...
 $ cd4countwk: int  241 137 325 283 235 219 634 465 111 316 ...
 $ pred      : Factor w/ 2 levels "Placebo","Prednisolone": 2 2 2 2 2 2 2 2 2 2 ...
 $ outcome   : int  0 0 0 0 0 0 0 0 0 0 ...
 $ surv4     : int  1137 1137 1137 1137 1097 1097 1097 1097 1129 1129 ..

Data structure  for the survival analysis is as 
'data.frame':	116 obs. of  6 variables:
 $ id1       : int  1011555 1011558 1011568 1011575 1011577 1011581 1011592 1011957 1011961 1011964 ...
 $ week      : int  0 0 0 0 0 0 0 0 0 0 ...
 $ cd4countwk: int  241 235 111 68 146 516 150 64 13 220 ...
 $ outcome   : int  0 0 0 0 0 0 0 0 0 0 ...
 $ surv4     : int  1137 1097 1129 1099 634 1137 1100 729 731 736 ...
 $ pred      : int  1 1 1 0 1 1 0 1 0 0 …


Thanks
Isaac