2015 Toyota Corolla P0304 Misfire While Driving - Solution & Diagnosis

I'm experiencing a persistent misfire issue in my 2015 Toyota Corolla with engine code P0304, indicating a misfire detected in cylinder 4. The problem first appeared during highway driving when the check engine light and track off warning illuminated. After turning off the engine for one minute, the symptoms returned—both lights remain on even after restarting. I've already replaced both the spark plugs and fuel injector for cylinder 4, but the issue persists. Any insights or troubleshooting steps would be greatly appreciated to resolve this ongoing problem in my 1.8L engine.