If you’re encountering a “function not found” error on a web page despite the function being present, there are several possible reasons for this issue. Here are steps to troubleshoot and address the problem:

1. Check Function Existence:
   • Confirm that the function is indeed defined in your code. Ensure that there are no typos in the function name, and it is declared in a scope accessible from where it is called.
2. Check Function Scope:
   • Verify that the function is defined in the correct scope. If the function is supposed to be a global function, make sure it is not encapsulated within another function or block that restricts its scope.
3. Review JavaScript Console:
   • Open your browser’s developer console (usually accessible by pressing F12 or right-clicking and selecting “Inspect”), and navigate to the “Console” tab. Look for any error messages related to the missing function. JavaScript errors will be displayed here.
4. Check Script Loading Order:
   • Ensure that the script containing the function is loaded before the code that calls the function. If the function is defined in an external script, make sure the script is included in the HTML before the script that calls the function.
5. Check Script Loading Errors:
   • Inspect the Network tab in your browser’s developer tools to check for any script loading errors. Ensure that all scripts are loaded successfully without any 404 errors.
6. Verify Script Inclusion:
   • Confirm that the script containing the function is properly included in the HTML file. Check for correct script tags and paths.
7. Clear Browser Cache:
   • Clear your browser’s cache to ensure that you are loading the latest version of your scripts. Cached scripts may lead to inconsistencies between the code you see and the code that is actually executed.
8. Check Script File Extensions:
   • Ensure that the file extension of the script containing the function is correct (e.g., .js for JavaScript files). Incorrect file extensions can lead to script loading issues.
9. Debugging Tools:
   • Use browser debugging tools to set breakpoints or add console.log statements to trace the flow of your code. This can help identify where the function is expected to be called and whether it is encountering any issues.
10. Verify Function Call:
    • Double-check the function call. Ensure that the function is being called with the correct syntax and parameters, if any. Incorrect function calls can lead to errors.
11. Inspect JavaScript Errors:
    • If there are other JavaScript errors on the page, they may be preventing the execution of subsequent scripts. Resolve any existing errors to see if it resolves the “function not found” issue.
12. Browser Compatibility:
    • Check if the function relies on features that might not be supported in certain browsers. Ensure that your code is compatible with the browsers you are targeting.

By systematically checking these aspects, you should be able to identify the cause of the “function not found” error and take appropriate actions to resolve it. If the issue persists, providing more details about your code and any error messages would help in offering more specific guidance.