Problem with data-elements (list) in custom data entry forms

we have system with no of DE’s. some of them have ‘gender-age’ category-combination and others have ‘default’ category-combination. while creating custom data entry form, the DE’s with ‘default’ category-combination are shown only in the ‘Totals’ list instead of ‘Data elements’ list for data entry field.
at the back-end the api seems to be getting only datalelement’ id e.g. ‘CpRyFIFaPR9’ rather than ‘CpRyFIFaPR9.HllvX50cXC0’ with dot and appended id for the ‘default’ category-option-combination. as a result the dataelement is placed in ‘Totals’ rather than ‘Data elements’ list.

Please help me, if am missing some thing in the workflow while creating DE’s, Category. Options.etc. or i am missing some other configuration in dhis2 or its a bug in certain version of dhis2. (v2.27)