struggling with accurate carrier IP detection on mobile, any tips?

hey everyone! i'm super new to this, just launched a tiny SaaS and trying to add some basic geo-personalization features. for desktop users on Wi-Fi, my current ip detection works pretty well, but i'm having a real headache with mobile users.

the IP addresses i'm getting for users on mobile data are often way off. instead of their actual location, i'm seeing IPs from what seems like their mobile carrier's central proxy or VPN, sometimes hundreds of miles away. this makes accurate carrier IP detection impossible for my use case.

here's what i've tried so far:

• i'm using a well-known IP geolocation API (won't name it directly but it's one of the big ones). it's great for regular ips.

• i've tried checking x-forwarded-for headers, but often they're either not present or also show proxy IPs.

• i've considered client-side geolocation via browser APIs, but i'd really prefer a server-side solution for consistency and privacy.

my questions and what i need help with:

• is server-side mobile IP detection inherently unreliable for precise geo-targeting due to how mobile networks operate?

• are there specific services or techniques that are known to perform better for carrier IP accuracy, even with mobile data?

• am i missing something fundamental about how mobile IPs are handled? it feels like i'm hitting a wall here.

anyone faced this before? any guidance for a noob would be awesome!