Sms received from AATRADING about debit order to run off my account

I received a sms a few minutes ago that AATRADING lodged a R99 debit order for date 19/01/2019 on my acc. I should call ********** 997 with Ref AAT35097. I DID NOT authorize any such debit order, don't even know who AATRADING is. The said contact number is constantly engaged!