I’m running a legacy application that grants database access through a Google Authenticator one-time-password flow written in PHP roughly fifteen years ago. After a recent code update by another engineer, I discovered the login step fails whenever the user enters the OTP, redirecting to the original login screen. I believe it no longer validates because of version-specific changes in the language and supporting libraries. What I need now is a clean refactor—or if faster, a well-contained patch—that restores full OTP generation and verification under PHP and remains stable when later versions are released. You’re free to bring in current open-source TOTP libraries or roll a lightweight class of your own, as long as the final solution: • Works out of the box without deprecation warnings • Authenticates against the existing Google Authenticator secrets already stored in my DB • Requires no schema changes to that 15-year-old database • Is delivered as self-contained code with clear upgrade notes so future updates won’t break authentication again I’m looking to have this fixed ASAP; once your code is in place I’ll test and if the OTP validates correctly, the job is done. Must be able to communicate in English well