Hi RifqiEryaJody,
Thank you for the request admin with the information given.
For this issue, we would like to confirm what is your role at the group (teams), are you an owner or members? If you could tell us a little bit more, that will be appreciated. More importantly, could you tell us in what scenario you get this messages, when you are in the teams channel chat, 1:1 chat or at the teams meeting you had the "You've been muted, so you can't start a conversation"?
If you are not owner or as an owner, let another owner change your account to member -> mute then unmute you -> wait for a while and change you back to owner. If you are a member, you can do the reverse.
If the issue still persists, we would like to know if other members in the group having the same issue as yours.
We are looking forward once you got any updates or any test results. Please feel free to ask any questions so we shall follow you up.
Yours Sincerely,
George