Problem with p p > h > z z [QCD] decay

When I run generate_events for this process I get the error message, "Error detected in "generate_events run_01"" and the error message "MadGraph5Error : Failed the initialzation of loop-induced matrix element 'PVO_0_1_gg_h_zz' (trying with a maximum of 15 PS points". It makes no difference whether i have pythia etc turned on or off.

Thanks

David