Can I see chats from before I join the team chat?
Members who join later can see previous chats if the team chat host enables the Team Data and Previous Data settings.
Contact the host and ask if these features are enabled in your team chatroom.

[How to enable features]
• Go to KakaoTalk > team chatroom > upper right menu (≡) > Settings (gear icon) > Team Settings > Manage Access > Previous Data

Kakao is unable to confirm the team chat's chat backup data or whether individual team chats use the Previous Data feature. Please contact the host for more information.