I created a sandbox of license type 'developer' and while after logging in from the sandbox login page, I'm stuck at the verification page as I don't get any verification code in my phone. I tried troubleshooting by rebooting my phone. I tried resending the code several times. I also tried the salesforce authenticator to generate temporary code for myself(I have system administrator rights) but the temporary code didn't work( the generated code was also longer than the one expected by the verification page). What do I do to access the sandbox environment?