​PH04 Problems with Automatic Mode and Problems with Dyson Customer Center in China

I am Korean.
I live in China and bought a Dyson PH04 air purifier in China.

Once, there was a strange noise from the vent, so I ordered it to be worn at the center.
I almost wanted to fight with the telephone consultant staff, so I finally got a new one.

However, the newly replaced product also had problems.
In automatic mode, the machine works very loudly even when the sensor light is already green. I had the center wear number 2 for this problem.
The result of the inspection at the center said, "The product is not in product condition."
Strong winds can occur even when the sensor is green.

However, I didn't understand how strong the wind was (10/10) even when it was already green. The Chinese staff repeatedly answered like a machine to see if there was a Dyson customer service manual or something.

I recorded the situation of the product. The strong wind (10/10) is still maintained even though the sensor light has already passed more than 10 hours. I explained to the counselor that this product is not normal.

However, as expected, the Chinese employees answered without caring like machines.

"Even in green conditions, there may be strong winds to maintain air quality, and strong winds may continue to occur depending on the environment of the customer's plan."

Some Dyson customer response manual read it as if it were a Bible.

I'm a normal person and 10/10 of wind strength is close to the level of noise I almost don't want to hear. PH04 users will understand what I'm saying. It's too loud in the main room to use the machine.

What is the meaning of using an air purifier to clean the air
What is buying and drinking good water? It will be for a healthier life. The air is purified, but if the loud noise increases stress, is it really meaningful to use an air purifier?

With the Chinese counselor already talking about green sensors, strong winds can continue. I don't understand the answer that this is normal, and I couldn't believe that Dyson in the United States produces such a low quality product. Anyway, I'm so disappointed with the Dyson product and customer service quality.

And a few days later
I have found that this problem is more likely to be a sensor failure, not a continuous strong wind, to maintain air quality in automatic mode.

Again, the machine was spinning in strong winds with the automatic mode green light. (Green for more than 7 hours) When I turned off the automatic mode with the remote control and kept on going, the air volume suddenly decreased significantly in the automatic mode. (0/10)

It's like hitting a man in the back of his head who's mesmerized by a sexy woman to wake up.

If I summarize the contents

The current state of the machine has no problem recognizing bad air. However, after the air has already been purified and becomes a pleasant environment, it has to change from rapid to less, and this process is broken. That's why it continues to operate stupidly with strong winds in a green state.

I'm going to recognize this problem
I contacted the Chinese customer center and ordered the product back to the customer center with consent. However, the customer reception environment at the Chinese customer site was a mess, so I didn't check the sensor, which is the main problem this time, and notified me of a very stupid and simple information that strong winds were normal when it was green, and sent the product without consent from me.

I finally couldn't communicate with the Chinese customer center anymore, so I filed it with the China Consumer Protection Agency. I don't know. Whether the China Consumer Protection Agency will be aware of such a complicated situation and protect consumers positively.

I think Dyson's U.S. headquarters should also know the actual situation of Chinese customer center employees who read customer response manuals like robots without understanding people's minds, so I leave it here.

The price of the product is over 1000 dollars, but I have not been able to utilize any of this cost yet.

What should I do?