you ask to set the tot pop for site but if "site" means health center or facility or the location of the your vaccination then it is not possible to define the tot pop at this level.
If by site you mean health district or commune... then you will have in the area multiple locations where the vaccination will be conducted but still not population by location
dhis2
Username: catherine.bachy
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URL: https://dev.hmisocba.msf.es/dhis/api/apps/Reactive-Vaccination/index.html#/campaign-configuration
you ask to set the tot pop for site but if "site" means health center or facility or the location of the your vaccination then it is not possible to define the tot pop at this level. If by site you mean health district or commune... then you will have in the area multiple locations where the vaccination will be conducted but still not population by location