Uncaught SyntaxError: "undefined" is not valid JSON - JavaScript JSON.parse() Error Troubleshooting

This error occurs when the JavaScript "JSON.parse()" function is called with an invalid JSON string. In this case, the error is being thrown in the "user.js" module of the store.

To fix this issue, you need to ensure that the JSON string being passed to "JSON.parse()" is valid JSON. Check the code in "user.js" and make sure that the JSON string being parsed is correctly formatted.

If you provide the code in "user.js", I can help you further in identifying the issue and providing a solution.