WhatsApp Setup Wizard Won't Show SMS Option After Account Hack

I am using a Zong number in Karachi and my WhatsApp account linked to this number has been hacked and stolen. When I try to set up or recover my WhatsApp account, the setup wizard does not even show the SMS verification option, so I cannot receive any code and my WhatsApp is not working at all. This situation is causing me serious inconvenience because I cannot use WhatsApp for my daily communication and I am worried that someone else may be using my number and account without my permission. I kindly request your support to help me regain access to my WhatsApp account and to check whether there is any issue related to my number, incoming verification messages, or anything else that could be blocking the normal recovery process. I expect this problem to be investigated urgently and for you to guide me clearly on what can be done so that I can safely use my WhatsApp again with my Zong number.