Secondary CommandBuffer execution - framebuffer attachment clearing

I am working on a Vulkan deferred rendering engine. I have problems when executing secondary command buffers within a primary commandbuffer. The color attachments of the offsreen framebuffer are kind of cleared in some unintential way. When i execute my List of secondary commandbuffers within the primary commandbuffer I can only see the object which was first executed within the secondary command buffer list. So, what I can see on the screen (resp. in the offscreen framebuffer color attachment) is ONLY the first object which was drawn with a secondary commandbuffer. All of the other objects in the list are discarded, and I don’t know why. If I change the ordering of the objects, again only the first objects is rendered to the color attachment.
Btw. I have a depth attachment and depthTest = true.
Is there anyone who knows the issue with secondary command buffer? :confused:
Thanks very much for every help!