Bad billing and service

I took out oneplan police after cancelling my Discovery medical aid I had for years. When I started with oneplan they debited my bank account for R725.00 which was for my premium R1425 300 for the 2 cards I ordered on my plan. On the 09 February R150 , 26 February R1425 and 26 February R150 was debited from my account and that was the agreement. Today I get an sms saying a debit order fro R1835 is due on my account. First question is when did my plan go up from R1425 to R1835 without any information sent to me or an update. When I called in this morning a lady tells me the is an increase on my policy because oneplan added more benefits to my plan and now the question comes to say who the hell authorised an increase on my plan without me saying yes or no? so oneplan controls me and my finances? is oneplan a legitimate business or it's just about beating the bushes? Are the clients important to oneplan or oneplan is more important than the clients?<br> <br> Now I want to down grade my plan to a lower plan since oneplan cares less about the clients and I hope the R725 I paid should either be enough to cover me for the three or four months maybe?