Hi Jay, your Firefox identified itself as version 115 running on Windows 8.1. Is that right? You can confirm your exact version number in the first table on the Troubleshooting Information page ([[Use the Troubleshooting Information page to help fix Firefox issues]]). The Extended Support Release of Firefox 115 is the latest version of Firefox for Windows 7, 8, and 8.1. By now Windows 10-11 users are up to Firefox 139, so your version does look old to websites. I don't know whether it will help but you can set Firefox 115 to lie about your Firefox version number. This might fool Amazon. Here's how: (1) In a new tab, type or paste '''about:config''' in the address bar and press Enter/Return. Click the button accepting the risk. ''More info on about:config:'' [[Configuration Editor for Firefox]]. ''The moderators would like us to remind you that changes made through this back door aren't fully supported.'' (2) In the search box in the page, type or paste '''forceVersion''' and pause while the list is filtered (3) Double-click the '''network.http.useragent.forceVersion''' preference to display an editing field, and change the value to '''128''' then press Enter/Return or click the blue check mark button to save the change. If you try Prime again in a new tab, does it still give you the same message, or does something else happen now?