Not receiving verification code from whatsapp

Recently shifted to IOS from Android. While everything went well the whatsapp has give me a headache. I had used Move to IOS app to transfer including whatsapp. While everything else worked, whatsapp did not.

I am stuck as i am not receiving Code for the past 4 days. I did go thru a lot of ways as suggested in google and reddit but none has worked for me. I am almost in the verge of losing hopes as i m tired of waiting every 8 hrs for an sms code and only to realize that it wont come. call option too does not work.

Can anybody advise a foolproof way to receive OTP.