Bankmed doesn't consider cancer pre-screening blood tests important

I had blood tests done on 25 July 2018 as per my doctor’s instruction. The claim was submitted by Lancet to Bankmed, and Bankmed paid Lancet as per the e-mail I received from Bankmed on 30 July 2018. However, the PSA test costing R207.50 was not paid for, not even from my MSA. The reason given by Bankmed is that I did not authorise it with Bankmed first before I had the test done (code 511). Can you please explain why I should first authorise it with Bankmed when my doctor, who has more than 35 years of experience in the medical field, has requested that I have the test. Surely cancer pre-screening tests are something Bankmed would support without authorisation being required? I have more than R62000 in my MSA and hardly claim from Bankmed, because Bankmed pays for nothing (i have to pay for my doctor's visits from MSA, chronic medication from MSA, prescribed medicine from MSA, blood tests from MSA etc). I know it is a small amount but its the principle of the matter.