Double Debited for online shopping

I recently purchased online via Woolworths online app, my bank account was immediately debit for the groceries which was on the 23 july and my delivery happened at 4.45pm on the 30th july , and my bank account was debit again for the same purchase. I tried on numerous times to call the customer service number and the voice recording prompts due to the volume of calls they cannot help me and the call disconnect. Woolworths being such a huge and leading consortium in the food market, I would assume they are adequately equipped for this online shopping. Maybe they should start by hiring capably,suitable staff for their industry so their name could be upheld, the caliber and mantality of their frontrunners are sadly appalling hence I thought online shopping with them would be better, unfortunately my happiness was shortlived on my first online purchase.