If using a version of the unofficial application of WhatsApp and has your account is blocked temporarily.
In the FAQ page, it says the messaging app owned by Facebook that people who use modified versions of the application like WhatsApp Plus and WhatsApp golden or other, they will receive a notification within the app that their account is banned temporarily.
It is unclear exactly when the app started to ban people who use apps to rate, but monitor our complaints on Twitter and social networking sites users that their accounts had been banned.
Accounts not banned permanently. You only need to switch and use the version of WhatsApp official will cancel the ban.
Sources: FAQ – Twitter – Reddit