Double charging...

Pathetic service from Lancet. My son was in the hospital in May. Our medical aid does not pay Lancet directly, but pay us the amount and then we pay Lancet. I picked up that a bloodtest was charged for twice on our account. A test that does not need to be repeated. I tried to phone them,but they keep on saying the test was only done once. BUT they do not understand that I can see on the statement with the codes that it was done twice. And our medical aid refuses to pay for it twice... I eventually,after numerous emails,got a response where they also stated that it was only done once. I sent a reply 6 days ago stating,that if it was only done once,why are we being charged for it twice(I can see the exact codes and amounts for the tests). I have STILL not received a reply. Today we got another statement where that amount of those tests are the only money outstanding. As I went through the statement today, I picked up ANOTHER mistake. My son had his Covid test done 12 May, which the medical aid paid for. But on the statement it shows another Covid test for him that was done on the 13th, (Our medical aid paid for that too, but it is not right.) he did not have this test done. Why would we,if we got the results back on the 12th already? Lancet does not know what is going on. Its really pathetic!