Dear student,

Since you haven't received the OTP yet for SPPU  examination try to register through some other mobile number on the official website since this might be a network issue, usually the OTP is instantly sent but during certain connection problem or network issue the OTP gets too delayed so try registering through another mobile number. Or also an option for resend OTP will be available once you register also the same OTP goes on registered email ID so also check your mail once.