ERROR #1000 in the input data: Incorrect data in field #2

When I try to check the model in OptiStruct, it gives me the following error:

** See next message about line 34 from file:
     D:/Users/eRacing/Desktop/PFGmaria/Prueba_Altair_Neumatico.fem
  'DMIGMOD'
  
 This line was interpreted as:
   34:DMIGMOD
  
 *** ERROR # 1000 *** in the input data:
 Incorrect data in field # 2.
  Expected STRING, found  BLANK.

Should I define anything in the DMIGMOD card? 

Thanks in advance