Karcher SE 5.100 Repeatedly Failed and Service Could Not Fix the Problem

I purchased a Karcher SE 5.100 carpet cleaner from Karcher Online about two years ago. For the last six months, the machine has not been spraying water, so I have not been able to use it properly for cleaning. Because of this problem, I sent the product to authorized service twice. At the first service visit, they stated that there was no problem with the machine and returned it to me. When the problem continued, I sent it again, and this time they changed the water pump. However, about two weeks ago, when I wanted to clean my carpet, the same issue occurred again and the machine still did not spray water. I then called the call center, and today they called me back and claimed that I had used the machine without water, which I find unacceptable and inconsistent with my actual use and the recurring technical problem. Despite my repeated attempts to resolve this through service and customer service, the problem continues and I am not satisfied with either the product performance or the explanation given to me. My invoice number is FP22024000001013. Given that the same fault has recurred after service interventions and I have been unable to use the product as intended, I request a full refund for my Karcher SE 5.100 carpet cleaner.