There can be multiple reasons for this problem, so please check the below steps:
1. You should not be using a VPN on your device.
2. Your mobile network is strong.
3. If the network is good and you are still not getting OTP then check if you are able to receive other SMSes.
4. Try using Call OTP by clicking on the "Resend OTP" option
A. Click on "Resend OTP"
B. Now click on "Via Call"
If you still are not getting the OTP, raise a ticket for the same and we will ensure that your issue is resolved.