Panneau de douche 61 po avec pomme de douche réglable SPW8311

I purchased this shower panel in January 2021 for a renovation we were doing. It arrived promptly and well packaged. I was impressed with the look of the unit and the hardware. In May our contractors plumber finally got it plumbed and installed. We tested the water flow and all seemed fine. That is until I used it. It states the unit is preset at 38.5 ? or so C. In fact it went to well over 46C, and when I turned back the valve we had very little pressure. A couple of things here, learning how to adjust and set the pressure is a challenged, the Blue Ocean instructions are vague to say the least. So, got it set to 38.5C, however, when it reaches temperature the water pressure reduces to probably 30 percent of full full, turn it to cold and it drips. I have tried to find Blue Ocean Canada online to learn what to do, no luck. Spent a few hours online and found instructions to clean the valve, replace the valve, and as my plumber tells me, he can do nothing. To say I am disappointed is an understatement. I have called Wayfair only to be put on hold, and on hold, but an apology comes up and states they are experiencing heavier than normal calls. Did everyone buy a Thermostatic Shower. My hope is to hear from someone, with a solution. However, upon getting through with my call they were VERY accommodating, a new was shipped to me within days and it works as stated.