Getting a texture buffer have size 0

Trying to load a texture data, but always get GetBulkDataSize equal to 0

Here is my code

auto &CubeMaskMipMap = CubemapMask->PlatformData->Mips[0];
const void *CubeMaskRawImageData = CubeMaskMipMap.BulkData.LockReadOnly();
int CubeMaskSize = CubeMaskMipMap.BulkData.GetBulkDataSize();
int CubeMaskItemSize = CubeMaskMipMap.BulkData.GetElementSize();

Calling this code from PostInitializeComponents() or BeginPlay() does not matter.
Calling CubeMaskMipMap.BulkData.ForceBulkDataResident(); does not produce any results either.

How can I get texture data? Any texture setting i am missing?