2002 Toyota Tacoma P0440 and P0446 Error After Replacement of EVAP System Components

Hi everyone, I'm looking for help with a recurring issue on my 2002 Toyota Tacoma 2.7L. I initially received diagnostic codes P0440 and P0442. The mechanic replaced: - EVAP Canister - Two valves (one at the canister, one near the engine) - A new gas cap purchased from a Toyota dealership After three months, the issue returned — now showing both P0440 and P0446. Despite performing a smoke test and confirming that all valves are functioning properly, the check engine light remains on. The mechanic advises continuing to drive the vehicle since no immediate performance issues have been observed, and it will pass the next inspection. Is there any known cause or troubleshooting step I'm missing for these specific codes? Any insights would be greatly appreciated! Thanks in advance.