The error is on data element NOT dataset. Since data elements have no start and end date, may be check if you are using category options (end date) on that particular data element (wdbCsuncOQ)
@viet thanks for this I have checked and had put in value to allow data entry for at two years in advance since these are targets but it still doesn’t allow for some of the data elements.
I experienced this issue today while importing data. Just make sure that the period format matches and that the open period is properly configured to suit.
Okay thanks @Maureen_Otini, I understand! Please check the instructions by @prosper above, and would you share the dhis2 version you are using as well as a screenshot of the error you are facing (just wondering if it might be helpful).