Do not link unknown Open
If an unknown person contacts you through WhatsApp, do not reply to him. Apart from this, if someone unknown shares any link with you, then do not open it. Never share your bank details with anyone. Never share if someone asks for Debit Card, Credit Card PIN and Internet Banking Password.
Do not download unknown files
If any media file has come from a new number, then never download it. There may be a virus in that file which can hack your account. Disable auto download in your phone. Go to WhatsApp’s Settings and change the settings by going to Data and Storage Usage. This will not download any file automatically.
deactivate the account immediately
Do not share the OTP that comes in the phone for any small or big cash transaction whether it is done from bank account or e-wallet with anyone. If you lose your phone, first deactivate WhatsApp. For this, you can email email@example.com or login to WhatsApp from another phone and then delete or deactivate WhatsApp.
Avoid the use of public Wi-Fi
After changing the phone, first go to the phone’s settings and delete all the data on the phone and reset it to the factory version so that your information is safe . Avoid using unknown or public Wi-Fi, it increases the chances of hacking. Many times hackers can hack your phone online fraud with Wi-Fi.