If once you receive your security code you cannot reach a page to enter it, you may need to clear your cache. Please select the instructions for your particular browser if you need help doing that:
Chrome on iPhone, computer, or android device: https://support.google.com/accounts/answer/32050?hl=en&co=GENIE.Platform%3DDesktop
Safari on iPhone: https://support.apple.com/en-us/HT201265
Internet Explorer: https://kb.wisc.edu/helpdesk/page.php?id=15141