New Hisense dishwasher HV671C60UK issue

Hi all,

I am lookong for some help with an issue with my new hisense dishwasher. I only had it installed a couple of weeks ago and this issue has now occurred twice in two weeks and I feel like I am missing somethint here. So the day I had the dishwasher installed, the engineer turned it on and showed that its all working fine. Later in the day when I filled it with dishes, I tried to turn it on and there was no power at all and wouldnt turn on. All was plugged in and switched on but there was no power and the panel wouldnt light up. So I called the engineer in and he checked everything, he couldnt figure out the problem and thought its a manufacturers fault so contact Hisense. The engineer left the dishwasher unplugged at that point. I called Hisense and few days later their engineer came, plugged in the dishwasher turned it on and it powered up like nothing happened. Made me look like an idiot but oh well I was glad it was working. 2 weeks later, yesterday I opened the dishwasher in the morning to empty it and noticed some water at the bottom which hadnt been drained. I read through the manual and it said that the filter may need cleaning so i turned the dishwasher off and took the filter out but filter was clean. I then thought perhaps the cycle didnt complete last night for whatever reason and tried to turn it back on and it wouldnt come back on, exactly like the issue that occured on the first day of installation. I tried resetting it from the breaker but same, it does not power up. The plug is behind the dishwasher so I cant get to it but pretty sure there is no fault there because i had my electrics checked when the Hisense engineer came 2 weeks ago. I think I am not doing something right which causes it to go in some sort of sleep or safety mode but the user manual doesnt state anything.

Does anyone know what could be the reason or has experienced something similar? I have called the Hisense engineer out again but wanted to check if its a user error rather than a mechanical fault.