Arrears??

I received an SMS asking me to contact TCR regarding my account ( not sure why i should be the one calling them)

Anyway, I called and I am told my account is in arrears for January as I did not pay and they gave me a grace period (Thabang says for 13 days). Since when do fees get charged during a grace period, also is it my doing that it was left active for that long? On my March statement on 3 March it says "bad debts written off" i made a payment of R599 on March 18 taking an advantage of the special "Reconnect at R499 for 1 month Discount offer ID:534" as per the email i received it said you will waive any outstanding arrears and reconnection fees i may owe?? I still don't understand the whole thing. Please can someone contact me in writing as none of this does not make sense.

Please also don't give me any grace period. If I don't pay on the due date, cut my services until I pay. I don't understand why I am incurring any charges while on the grace period.