Bad medical cover experience

Discovery delta essential core, thats the medical cover i recently took out with discovery, unlike other medical plans/aids they clearly stated the i am covered from the 1st payment and no waiting period.the only catch is that at any given time for full in hospital cover,you would need a referral from a gp but one visited at your cost. So this was my bad experience..i was given a emergency referral and was turned down ,even thou the in hospital cover is unlimited,they want to determine if my condition was preexisting,now define preexisting discovery, so if one had a bad cough 4 Months back and was only diagnosed with say a medical condition like tb on the 4th month,is the cough or the diagnosis prexisting? Similar to my case..i didn't see my issue as a emergency until the Doc found the need to refer me ,and anything could have happened to me afterwards,so the words NO WAITING PERIOD should be strictly adhered to,and should there be any other terms , please stipulate and not give patients the unpleasant rejection of medical treatment when needed .my personal experience,this is bad to a huge company like discovery.