Since Google search results are very dynamic, the position we report in our Rank Tracker might be way off by the time you check it, and there's no way to fight this.
This is especially true for any listing that's not ranking on the first page of Google.
Our research have shown that search listings below the first page of Google tend to fluctuate a lot more often than those on the front page.
Here are also a couple of points to consider when comparing our results with those of Google:
1. You must ensure you are using "Incognito" mode in your browser and you're logged out from your Google account - all of that to avoid the "personalisation" of Google's search results.
2. You must ensure that your IP address location is matching the location that you're tracking in Ahrefs Rank Tracker tool. You can do it here - https://www.whatismyip.com/