Claim submission process failure

Good day, I submitted without any inital success an invoice for reimbur*****t for medical expenses incurred during and after my mothers hospitalisation in September this year. I spoke to a number of different agents who always asked for additional information, promising to call with feedback after the claims were processed( which never happened) and nobody ever replies to any of my emails regarding the outcome. I am fully consented and I have explicitly asked any one person who is able to come across my emails to request verbal consent from PP or SP if need be but to no avail. I don't have a problem calling into the callcentre if I know I'll speak so someone who can follow member remarks, find relevant correspondence and give me feedback without putting me on hold for countless minutes. Please help. ID supp**** for PP but claim pertaining to SP for service provider Oxygen and General.