"GUARANTEED SAME DAY DELIVERY", No Delivery

I paid for same-day delivery, and my order never arrived. I am appalled. They have now shut down their phone lines so I can't even contact them - I have to wait up to 72 hours for an email response. But I repeat - I PAID for same-day delivery, which you "guarantee". You know this is false advertising, right?? Where the hell is my package?? I've been such a loyal customer for years but this is NOT on!