It takes a long time to optimize in the Tizen OS. I suggest you wait a few hours and see if the problem is solved. Otherwise, Reboot of the phone sometimes fix this error but if it doesn`t better uninstall and reinstall whatsapp to fix the error and deficiency. I suggest you forward your contacts to your email first because if you will reinstall whatsapp it can not save your contacts.
No this not the solution of this problem after 95 optimizing whatsapp after some time automatically it stop and then when I again on the whatsapp again it's start initializing from 1 nd again stop at 95 so what to do know