ustsuw errors for AMB74 estimation ; but none for fluence estimation

Hi All
I am getting the following error when i use the 'ustsuw' to access the data
written to the file *fort.37.
-------------------error message-------------------------
 Type the input file: dose001_fort.37
 Estimation of neutron dose
 DATE: 9/12/ 8, TIME: 13:59:43
 10.
 10
Subscript out of range on file line 243, procedure ustsuw.f/MAIN.
Attempt to access the 3001-th element of variable accumg.
Abgebrochen
*----------------------------end of error message-----------
I tried changing the "PARAMETER (NMXEBN =2500 ) to different values (at
present at 2500) and tried cutting down the number of energy bins to
differet sizes. I have had no problems before with 600 bins using the same
program. Infact on a different detetcor it runs very well. The input part of
this scoring is attached as 'input_part1.txt'. However, similar input with
fluence scoring instead of dose runs very well even with larger energy bins
(input part attached as 'input_part2.txt').
Both refers to the same detector but scoring different quantities.

Is there a parameter that can be changed in the ustsuw.f that can solve
this?

Thanks for all the help
Best Regards
Sunil