TOOK MY MONEY!!!!!!!!!!

I am so angry with Fedhealth. I was with Topmed and they joined with Fedhealth. I akways paid Topmed manually and did not have a debit order. Fedhealth debited me, without my authorisation (Did not see notification) and I did do a manual payment from another account. I requested a refund for the one payment. I was told I would get the full refund within 7-10 Days. This morning they short paid me by R2600. I called to ask why and they told me I owed Topmed money regarding something to do with my savings. WHY DIDNT THEY MENTION THAT BEFORE!! I have never received any correspondence from Topmed about me owing money. I have never missed a payment with Topmed and never short payed anything and its the first time I am hearing of it. I am so ANGRY. How can they just take money like that without communicating with me.