Topology optimisation - impossible result

Hello Simulia community,

I am faced with an issue using topology optimisation which has bothered me a few times. 

I am trying to minimise the mass from the part in the first picture (clamped on the end holes and loaded at the middle node) using Structural Generative Design, and specifying an area around the holes which must be preserved. After playing with a few options and Boundary conditions, I always seem to get a result which satisfies the conditions but is obviously impossible as it doesn't even link all the preserved parts together (therefore the part is rendered useless). I feel like I am missing something but after a bit of research and tests, I can't seem to find how to get around this issue.