Miele G 5000 SCU Active (Built-Under, Brilliant White)

I owned a Miele dishwasher for 15 years and was very happy with its reliability and performance, which is why I chose to purchase another Miele dishwasher 4 days ago. Unfortunately, my experience with the new Miele dishwasher has been extremely disappointing. The new Miele dishwasher was delivered and installed by Miele 2 days ago. The dishwasher stopped and powered down during the first two cycles shortly after installation - but would power back up after a few minutes or so. I only used the new Miele dishwasher twice before it failed completely. Now it will not work at all, (or turn back on). The attached video shows the issue occurring. I was also disappointed with the wash performance, particularly the drying results, which were very poor compared to my previous Miele dishwasher. I contacted Miele Customer Support regarding the issue (ie that it won't turn on or start) and was advised they will organise a technician to assess. However I was not given a time or date when this might occur. Instead, I was instructed to wait until someone calls me back. However, considering I previously waited 6 weeks for a Miele technician to assess my old dishwasher, I am very concerned about the level of after-sales service and support I may receive this time around. At this stage, both the product reliability and customer service experience have been extremely disappointing, especially given Miele’s premium pricing and reputation.