Field doesn't exist

[gef]

Hi all,

I keep getting this error message and I have been trying to find out  
why this is telling me that, it's a really really simple script and  
the error message doesn't seems to make sense since there is a field  
donorID. I really don't know what cause the problem.

thisDonorID  = «Record Number»
thisDonorName = FirstName
thisDonorLast = LastName


     openfile "donation"
     openform "donation list"
  select donorID = thisDonorID