WhatsApp blocked

I have been Been using whatsapp for so long with no problem, so yesterday in the morning I noticed my whatsapp was not working I request for a review later when I was checking my status it says I should register a new number which I can not afford too due to Important chats and contacts on the number, I registered using that number for work, personal information. I really need help with reopening my old app I don't know and understand why am being locked out of my app.