Firebase auth auto fetch otp not working

Earlier while creating app with firebase auth, after requesting otp n when otp arrives app automatically detect and verifies it. but now its not working that way, i have to manually enter otp to verify, help with it

Firebase auth should automatically read the OTP and let the user continue sign on process. I’m not sure what’s wrong.

There is an alternate way to achieve this is as below:

But, Google Play does not allow apps with Texting functionality, untill your app can function as a default texting application.