Internal Network Domain Problem (Apache2, Pi-hole)

Hey, I am hosting a website and Pi-hole on my Raspberry Pi. The website is accessible to anyone on the internet and operates correctly; however, for some reason, I cannot access it locally. Within the LAN, it seems to work intermittently, and I cannot access it at all over Wi-Fi. The browser displays a 'connection timed out' error. The Raspberry Pi is correctly registered as a DHCP server in the router. Unfortunately, I have tried various solutions and still do not know what the issue could be.