Cheated by Discovery Health Medical Scheme

I am a member of the Discovery Health Medical Scheme, enrolled in the Classic Smart Plan option. On 19 March, I consulted a General Practitioner who referred me for an ultrasound, which revealed Deep Vein Thrombosis (DVT) in my leg. The attending doctor at the emergency room recommended hospitalization. As the initial hospital was not part of the Smart Plan Network, they assisted in finding a Vascular Surgeon within the network. After exploring several options, they located the surgeon at a network hospital. Due to the risk of the blood clot dislodging, the emergency room insisted that I be transported by ambulance. I was admitted to the hospital and underwent another ultrasound the following day, ordered by the surgeon. The results showed no blood flow in four arteries and monophasic flow in five others. I was discharged on 21 March with a prescription. To ensure coverage, I opted not to use the hospital dispensary and instead went to a network pharmacy. However, the claim was rejected due to an issue with the active ingredients, according to the pharmacist. To avoid delays in my treatment, I paid for the prescription out of pocket. This morning, I spent over an hour on the phone with Discovery, only to be informed that the rejection was because the surgeon was not part of the Smart Plan Network. I am struggling to understand this decision. My question is: who was supposed to issue the prescription? Was I expected to receive treatment from one practitioner and then request another practitioner, unfami**** with my case, to issue the prescription? I would appreciate clarification on this matter