ERROR # 1000 and TSTEP

Hi, my error message is as follows.

*** See next message about line 132233 from file:
     D:/DATA/gslee/wonut2/wonut2.fem
  'TSTEP          90       0.0'

 This line was interpreted as:
 132233:TSTEP, 9, 0, 0.0

 *** ERROR # 1000 *** in the input data:
 Incorrect data in field # 3.
  Expected INT > 0 or blank, found  INTEGER (0).

 *** ERROR # 1000 *** in the input data:
 Incorrect data in field # 4.
  Expected REAL > 0 or blank, found  REAL (0).

I don't know how to deal with this error.

What is the meaing of 'field'?

Thanks.