Proxy doesn't work on cellular internet

[mintydev789]

I have set up a Shadowsocks proxy server on a VPS using shadowsocks-libev, and I'm connecting to it from Shadowsocks Android. It works perfectly on Wi-Fi, but for some reason it doesn't work at all over cellular internet. It's able to establish a connection and do a successful handshake, and I can see bytes going both up and down. However, when I try to connect to any website, it's completely unable to connect. This is my server config:

{
    "server":"0.0.0.0",
    "mode":"tcp_and_udp",
    "server_port":443,
    "password":"...",
    "timeout":300,
    "method":"..."
}

On my Android device I have the correct server IP, server port 443, the correct password and encryption algorithm, and I'm running it in run everything mode. Remote DNS is set to 8.8.8.8, and I don't have any plugins (I don't know how they work). In the app's settings I have service mode: VPN, SOCKS5 proxy port 1080, local DNS port 5450 (I don't understand the point of this; doesn't the remote DNS feature route all DNS requests through the proxy too?) and Transproxy port: 8200 (also don't get what this does).

One thought I had was that this is a DNS issue, and the other one was that Shadowsocks is also relying on a second port besides 443 (in my case), and my mobile carrier only allows traffic over 53, 80, and 443. Regardless, I've now done countless amounts of digging and cannot understand the issue.

Edit: I found another clue. When I establish an SS connection over cellular and try to access google.com by direct IP address (142.250.10.99), I first get told that it can't establish an HTTPS connection, so I tap continue and then it actually redirects me to google.com, then I get another HTTPS warning, I tap continue, and then it starts infinitely loading again, unable to connect. When I do the same thing over Wi-Fi, it just redirects me to google no problem, and the page loads. So I think it might be a DNS problem and/or an SSL problem. I also tested directly accessing a niche website that doesn't have HTTPS by IP address, and in that case I don't even get the redirect, just infinite loading. Perhaps my browser already had the google.com redirect cached.