Woolworths wont resolve my complaint about my sandal that broke

I sent several emails to the woolworths customer service complaining about my sandals that broke. I have also taken the sandal to the store and the manager advised me that they cannot help me because I do not have proof of purchase. I have been battling with the customer service people since I sent the email 2months ago. Terrible customer service received via email as well as store level. What must happen to my broken sandal? We spend so much money paying for the 'woolworths difference' yet the quality is not superior.