Apollo Pharmacy — Medicine delivered Late

Dear Sir,
My order number was #[protected]. I have ordered medicine on 2nd June and was assured to be delivered by 3rd June. But the medicine was delivered on 6th June. By that time I had already obtained the medicine from different shop. The delivered box is unopened. I requested to take the medicine back and give refund. Contacted their customer care to take back medicine but they are refusing the refund. Who can wait for medicine for 4 days? They had promised one day delivery.