CAN'T REGISTER WITH THIS PHONE NUMBER. YOU CAN ONLY REGISTER WITH THE NUMBER THAT WAS USED WITH WHATSAPP ON THIS PHONE

i am having an iPhone, iPhone 4, which i have already installed whatsApp there but i could not configure it because it says and i coat. " CAN'T REGISTER WITH THIS PHONE NUMBER. YOU CAN ONLY REGISTER WITH THE NUMBER THAT WAS USED WITH WHATSAPP ON THIS PHONE" . so now my question is whether is there anything that i can do to resolve this problem or if there is any software for me to download in my macBook Pro to resolve it you can send me thank you.

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