Not able to assign custom application exit name to application in BRFPlus

Hi Experts ,

We want to customize authority check in BRFPlus. We have implemented interface IF_FDT_APPLICATION_SETTINGS into custom class ZC_FDT_SDN_APPL_SETTINGS.

We have written code inside Authority_check method and activated this method in CONSTRUCTOR_CLASS.

from ABAP side everything is done and activated properly, only issue is in BRFPlus when we are trying to assign application exit class "ZC_FDT_SDN_APPL_SETTINGS" to the application in BRFPlus , we get authorization error saying "You are not authorized to activate the application ZAPPL_BRF".

We are not sure why this error is coming, Or do we need to assign standard application exit class i.e. "CL_FDT_SDN_APPL_SETTINGS" and it will automatically trigger its Z-implementation (i.e.ZC_FDT_SDN_APPL_SETTINGS).

We are new to BRFPlus. Please guide us to resolve this issue.

Thanks.

Regards,

Sanjana