P3421W, AE515 Soundbar, echo problem

When I am on any Teams all, all the participants commented that there is an echo when I am unmuted. Once I plug in my Plantronics headset, the echo disappears. The Soundbar is currently below my P3421W monitor which is 60cm away from me, the volume setting is usually at 31. I only started using the Soundbar back in March 22, 2021. Appreciate any assistance in removing the echo caused by the Soundbar.