MOM0 is undefined for structure <Anonymous>

[vvaleolivares]

Hello!
I am trying to convert moment to properties of the CO(1-0) emission line of some ALMA data, but I got this error;

% Tag name MOM0 is undefined for structure .
% Execution halted at: MOMENTS_CLASSIC 416 /johannes/alma/volivares/clumps/cpropstoo/moments_classic.pro
% CALC_PROPS_FROM_MOMENTS 165 /johannes/alma/volivares/clumps/cpropstoo/calc_props_from_moments.pro
% MOMENTS_TO_PROPS 68 /johannes/alma/volivares/clumps/cpropstoo/moments_to_props.pro
% CPROPSTOO_EXAMPLE 274 /johannes/alma/volivares/clumps/cpropstoo/cpropstoo_example.pro
% $MAIN$

Do you what could be the problem?
I tried with the IDL versions 8.3. and 8.5.1

Regards,
Valeria