Debited my money from my bank account

On the 20th Dec these people that i dont know they sent me an sms say on the 22nd of Dec they will be deducting R96.69 on my account .i tried to contact them as from that date they never pick up the phone .but today when i check my balance they took my money .what worries me now the bank is closed until tuesday where am i gonna reverse my money bcs my app is not working.Your MBS247 R96. 69 debit will run 22Dec 2017 sold by stratton ********** 093 ref STRATONVHOSTR ********** ********** 222 the only thing i want from them is my money plz Regards Tabela