Can't get cover closer than 300km radius for emergency!

I recently got married and moved and learned after some time that my closest network hospital is 300km away. I gave Discovery ample proof and documentation of my change of address so I can change to a plan that has a hospital within a closer range to me(seeing its for emergencies and all..) They denied my application based on the fact that I hadn't submitted it within three months.

Is this really such a big deal? The point of a hospital plan is for emergencies, surely the time line cant matter THAT much. If no one here helps me I will have to stop my premium immediately. Please sort this out for me. All my communication is on my profile. ID nr ***.