Is Lancet Laboratories committing *****?

My medical aid pays Lancet Laboratories. They also want me to pay for the same amount my medical aid paid for. Plainly put, they wanted rip me off. I complained. They said it was a misunderstanding. I had to take this explanation after they (with delays of their own) corrected my invoice to reflect only the money I should actually pay. <br> <br> I agreed to the correction and gave payment advice that payment of balance will be done by 29-09-2015. This has been fulfilled.<br> <br> However, I get confirmation that on 28-09-2015, Lancet Laboratories decided to take money from my account without my permission. I have not utilized any Lancet Laboratories services since. I have no additional invoices from Lancet Laboratories that I am aware of. This action by Lancet Lab would therefore fall under *****/Theft.<br> <br> You have overstepped the boundaries and nullified your explanation to my previous complaint. You have been paid. Why should Lancet Laboratories be taking money from my account when agreement includes payment advice showing when payment is scheduled to me done?