I'm Struggling to Buy a Single Sony WF-1000XM4 Bluetooth Headset

One of my Sony brand wf-1000xm4 model bluetooth headset was lost, so I called the customer representative to find out if I could only buy one, and they directed me to the authorized service and said that they might have it, so this time I called the authorized service and explained the situation, first they said that it was not sold alone, it was only available in full packages, so I said okay, and this time I wanted to know the package price of the full version, and this time they said that we do not have bluetooth headphones. Then I called the customer representative again and explained the situation, they asked me how they could help me, I said, can't you ask the main headquarters if they have it or not, they said that the authorized service asked and they told you so (it never happened, it was a momentary attempt to brush it off). The authorized service and the customer representative I met for the second time left me with the impression that they were trying to avoid me too much. I can say that it is a bit disappointing that a brand of years has such a staff.