Lying about the delivery date after a long wait

i complained about this supplier last week about taking long in repairing a cracked screen on my phone & after reporting to hello Peter they called immediately claiming that my phone was fixed and asked for my delivery address. that was on Wed last week, thursday & friday went by without a word from them. On Sat they called me that they will deliver on Monday & still i dont have my phone as we speak. When i phoned today they said it was scheduled to be delivered today (Tue) which is a lie as thats not what they said on sat when they called. What i want to know is why they have to promise lies. This is the 3rd Tue without my phone only cause of a cracked screen, if i had saved all this money i've been paying towards this insurance i would have fixed my phone in a day but it actually took them 3 weeks with my phone. I am so furious that I've decided to cancel this insurance. Its really not worth it & they've proved it.