we tried to RJ9 headset
https://www.amazon.com/gp/product/B00OUKCSEM
https://www.amazon.com/gp/product/B0741T9MD5
still having a problem while we talk, we can hear the voice, but caller does not hear our voice or hear breaking sound often
How to solve this problem?
Those two are cheap Chinese garbage. You get what you pay for.
Buy a USB-attached headset made by a major US telephone headset manufacturer, like Plantronics or Jabra.
For example: https://www.provantage.com/plantronics-85619-12~7PLA91JC.htm (https://www.provantage.com/plantronics-85619-12~7PLA91JC.htm)