Medshield not paying claims

So my husband had a stroke and is currently on Medshield. We practitioners i.e.e speech the******s submitted the invoices and they are not paying, as a result, we had to stop the sessions. When I email them they said they are busy investigating. It has been 2 months now and we have not had anything from them except that they are investigating. He is on PBM and I do not understand what the problem is. Can someone please help with OMBUDSMAN details - i think they are my last resort