Terrible Service

My wife was admitted in May 23 and April 24.Admitting doctor used Lancet to do blood tests. On Monday 19 May, I received an email from Lancet stating that I have an outstanding balance due to a medical aid shortfall. 1st claim is for May 2023 and 2nd for April 24.I have contacted medical aid who state that these are duplicate claims and all is in order from their side. Contacted Lancet who said that will relook at the account and should medical aid not pay, I am liable for a shortfall of R3660.50. How can Lancet withhold this account and expect the customer to do a reconciliation 2 years later. What kind of service is this. My account number is Y***7. My contact details is ***.