Some options:

• Use a SMS api service and let the code retrieve the SMS text from that service.

• Probably you do not want to test the TwoFactorAuth, but you want to test the application behind it. Consider building a backdoor which is only enabled in the test environment, so that you can bypass the TFA.

• I have read that people try to create an Appium test to retrieve the OTP so that could be another path: https://discuss.appium.io/t/how-to-read-otp-from-messages-using-appium/16949/8

Overall this is pretty challenging and makes the test setup complex and contain dependecies, there for I would go for the backdoor option.

Some options in my order of preference:

• Probably you do not want to test the TwoFactorAuth, but you want to test the application behind it. Consider building a backdoor which is only enabled in the test environment, so that you can bypass the TFA.

• Generate the OTP from code with OTP.Net: https://dev.to/j_sakamoto/selenium-testing---how-to-sign-in-to-two-factor-authentication-2joi

• I have read that people try to create an Appium test to retrieve the OTP so that could be another path: https://discuss.appium.io/t/how-to-read-otp-from-messages-using-appium/16949/8

• Use a SMS api service and let the code retrieve the SMS text from that service.

Overall this is pretty challenging and makes the test setup complex and contain dependecies.