[Eeglablist] Index exceeds the number of array elements

[zahra fotovatnia]

Hello all,
I have been creating a study using a script. I have this error. How can I fix it? thank you.
Rebuilding trial information structure for STUDYIndex exceeds the number of array elements (30).
Error in eeg_uniformepochinfo (line 95)    [tmpevent(indexevent).(difffield{index})] =    arraytmpinfo{allepochs(indexevent)};
Error in std_maketrialinfo (line 55)    ALLEEG(iEEG) = eeg_uniformepochinfo(ALLEEG(iEEG));
Error in std_checkset (line 220)            STUDY  = std_maketrialinfo(STUDY, ALLEEG); % some dataset do not            have trialinfo and
Error in std_editset (line 227)            STUDY = std_checkset(STUDY, ALLEEG);
Error in create_study (line 1)[STUDY ALLEEG] = std_editset( STUDY, [], 'name','my_study',...