Poly Voyager 4220 Series Stuck on mute once muted on Skype Call

Dear Sir/Madam,

I have a Poly Voyager 4220 Series and it's always stuck on mute whenever I muted it. The problem is, once muted, I couldn't unmute it anymore. The workaround is, I had to choose a different device, unmute, then choose Poly BT600 so I can speak again. But I don't have this problem with Microsoft Teams.

I used to have another headset Poly blackwire 3220 series, that works just fine. I can mute/unmute as I wish.