Found disallowed object type CrowdVolume help

I’m looking to find out why my map wont loadup to Fortnite for further testing

once it compiles and uploads i get this error

Found disallowed object type /Game/UEFNExposedAssets/Devices/ChildClasses/CrowdVolume/MI_CP_Device_CrowdVolume_Placed_01.MI_CP_Device_CrowdVolume_Placed_01

the strange thing is that my map Fully loaded up last night- all working i havent done any work on it but keep getting this error and Don’t know where to edit it.

can anyone help so i can get rid of the error please -point me in the right direction, my map is Crowd heavy and is a key element of it so i need to keep the crowd