Meshing

Hi,

I need to mesh a microfluidic model with different mesh sizes in different domains to save on computing time on the unimportant regions. Consequently, I've partitioned the model into different domains and used different mesh sizes in each. However, I keep getting an error that says, "failed to respect edge element on geometry edge"

I've tried subdividing this region into smaller domains but to no avail. Is there anything else I can do? Is there a edge specific refinement? I'm new to this.

Regards,

Arjun