Why am I not receiving OTP on my iPhone?

Open Settings > Apps > Messages and make sure RCS and MMS Messaging are turned on. If that doesn't help, you'll need to contact your carrier and text messages are a service they provide. Apple doesn't send messages, with the exception of iMessage, which are Apple device to Apple device.

How is it being sent to you? Text? Email? What exact iPhone model do you own and what is the current iOS running on the phone?

Hi

Did you find a fox for this? I have iPhone 15pro and suddenly not receiving OTP nothing has changed recently except for latest update