Terrible service - Fals advertising of discount

<p>On 12 July i received an sms saying "20% off all upgrades & add-ons to your ADT system".</p> <p>On 14 and 15 July I had upgrades done to my system - but the invoice showed no discount.</p> <p> </p> <p>Over the past month i have phoned ADT over 10 times to claim my discount before paying the invoice. They keep saying they will get back to me but nobody has done so.</p> <p> </p> <p>I want someone to contact me, to tell me how i can claim the discoun tthat was advertised - i will happily show anyone the sms.</p> <p>This service is terrible, as always. </p>