Daikin Gas Boiler Temperature Imbalance Problem

I bought a boiler from the Daikin Rize branch for my family, but it is constantly facing temperature balance problems. This year, the problem has been serious, and I have constantly discussed it with the seller, Meh***, and the related service. The seller and service team have inspected the boiler 5-6 times and claim there is no problem. As the problem persisted, I notified them, but their technical team and the seller's lack of professionalism did not resolve it. "There is no problem with the product, you are creating it yourself, and what you are doing is impolite," this Mehmet person told me on my most recent call. This type of language goes against our city's commercial ethics and trade tradition. Those representing the best brands in the sector in Anatolia must be carefully selected, and an individual dealer cannot become one simply because of financial eligibility. I'm hoping they'll take responsibility for their products and resolve the problem soon, or else I'll have to find another solution.