Palm Gardens Landscape

One of two Sylvester palm trees is nearly dead less than 5 months after install. Owner will not respond to my inquiries.
I purchased two Sylvester palm trees, plus installation, from Palm Gardens on 4/25/19. Material cost and install was $775 per tree ($500 per tree plus $275 install for each tree). Install was completed on 5/7/19. Irrigation bubblers were installed immediately following install and trees were watered 2 x daily as instructed. Within 3 months one tree was yellowing badly while the other was thriving. We have applied palm fertilizer and the condition of the tree did not improve but instead worsened. By the end of September only a handful of yellow/green palm fronds remained. I contacted Palm gardens by phone and explained the situation and our disappointment as it had been approximately five months since both palms were installed. In response the owner said "this has been a bad year for Sylvester palm trees, lots of people have had issues." He concluded by saying he would pull our info and get back to me "to see what he could do." No response afterward. I have followed up with two additional calls and multiple text messages on 10/10/19, 10/22/19 and again on 12/22/19. I have not received any response / follow up. Given the expense of the tree and install it seems the business should stand by their product for some amount of time, particularly when they admitted there have been issues with this particular tree type. Over the years we have purchased other trees and installations including irrigation and did not have challenges, but avoiding a customer and failing to resolve the issue after multiple attempts is unacceptable.