Handed over without ever receiving an account

This practice handed me over to a debt collection company without me ever receiving an account. There was a postal strike for months and they did not even have the decency to give me a phone call to tell me about the outstanding debt. I went to have blood drawn in March 2015 and was told that they handed me over and I have outstanding debt. I then paid the full amount. Now 3 months later I am receiving messages from the debt collection company saying that I owe money. This is ridiculous! 3 months and it is not updated. I will have to be half dead before I ever go here again. If I look at all the other complaints then it is no wonder this company does not respond.