Logging mistake

What a bad experience with lancet i went to lancet for bloods in Pretoria East hospital and the logger didn’t put an icd 10 code for the bloods and my medical aid paid half of the bill now lancet keeps calling for the payment i won’t pay for they are logger mistake i have been calling lancet to sort out this mass I’m even tired now for calling, where do I report this lab cause I’m really tired of this someone somewhere please assist