Why is my 'What is My Location?' tool showing incorrect geolocation data for some users?

hey everyone, so i just launched this 'What is My Location?' web tool a little while back, and for the most part, it's been working pretty well. users seem to find their current coordinates and map pretty accurately. but lately, we've been getting more and more reports about incorrect geolocation data for some users, and it's starting to become a real pain point.

our tool is designed to first try and get the user's location via the browser's native geolocation API. if they grant permission, great, we use that. but if they deny it, or if for some reason the browser API isn't available, we fall back to an IP lookup method. it's supposed to be a solid fallback, you know?

the issue we're seeing is pretty wild. some users are reporting their location being off by hundreds, sometimes even thousands of miles! it's especially prevalent on mobile networks, which i kinda expected to some extent, and definitely for users on VPNs. but we're even seeing it occasionally for desktop users who aren't on a VPN, and that's just baffling. they'll say they're in new york but the tool shows them in the middle of kansas or something, it's just so far off its not even funny.

we've tried a bunch of stuff to nail this down. first, we double-checked all the browser geolocation API permissions; everything seems configured right on our end. we also verified our Google Maps Geocoding API keys and usage limits, thinking maybe we were hitting a cap or something, but no, all good there. then we experimented with different IP geolocation databases, like maxmind, to see if that made a difference, but the results were still inconsistent. we also made sure our server-side IP detection logic is accurate, no weird proxy headers or anything getting confused. we even looked into network-specific issues, like how mobile carriers might route traffic through central points really far from the user's actual physical location, which could explain some of it, but not the sheer scale of the inaccuracy we're seeing.

so, my main question is, why would geolocation be so far off like this? are there common pitfalls with browser geolocation APIs or IP databases that we might be missing? i'm really trying to improve the overall geolocation accuracy for our users. do any of you have specific strategies for improving accuracy, especially for mobile users or those on VPNs, where the IP is often masked or routed unpredictably? i'm open to anything at this point, even if it means integrating another service or completely rethinking our fallback strategy. anyone faced this before? it's driving us a bit crazy trying to debug.