Fails to deliver my package, makes me wait the entire day, can't explain their failure

I ordered a package from Amazon and got both an email confirmation and an SMS stating the package would be delivered on 17 December. I then took a day off my busy schedule and was at the delivery address all day. My phone was with me all day. At no point did DPD Laser either a) ring the doorbell or b) try to phone me. There were no missed calls on my phone. Then, after waiting the entire day, I got a notification that they had been unsuccessful in delivering my parcel (no kidding!)

The call center put the phone down in my ear twice, after I queried this, and they could offer no reasonable explanation for their failure to delivery my package.