WhatsApp banning Groups
Regarding this issue, after contacting WhatsApp received an automatic reply states that banned from WhatsApp because of violating the Terms of Services, and no other human reply received. If a users changes the Group name & Group description related to malicious name the user got banned as per TnC. After that, he forcely need to change the mobile number for continue using the WhatsApp. Similarly, they lose their old account chat history.
WhatsApp detecting this activity from their server side and it completely automatic process. Similarly, WhatsApp will not read the chat messages and calls since its protected with End-to-End encryption. However, WhatsApp can able to read the meta description & meta title of a WhatsApp group.