clock_tree - innovus

Hello everybody,

I'm stuck for a few days with a specific error in my physical implementation for creating the clock tree.

When executing the command " ccopt_design",

I finally get the following error:

Downsizing: ...20% ...40% ...60% ...80% ..**ERROR: (IMPCCOPT-2215): The route/traversal graph for net 'clk' is not fully connected.

Can anyone tell me the best way to fix this kind of situation?

Thank you very much in advance