Browser Compatibility:

Try a Different Browser: Sometimes, certain browsers may have compatibility issues with certain websites. Try using a different browser like Chrome, Firefox, or Edge.
Update Your Browser: Make sure that your browser is up to date. Older versions have known bugs that can affect functionality.
Website Glitch :

Refresh the Page: Try refreshing the page to see if the problem goes away.
Clear Browser Cache and Cookies: In some cases, clearing your browser's cache and cookies will solve temporary problems.
File Format and Size:

Validate File Format: Confirm that your signature file is in a supported format (e.g., JPG, PNG, PDF).
Validate File Size: Confirm that the file size of your signature is within limits.
Internet Connection:

Poor or unstable internet connection is sometimes the cause of interruptions in file upload processes. Try using a stable internet.
If still experiencing a problem, you can try these:
Contact Technical Support: You may reach out to the technical support on the website. They can give you specific instructions for the troubleshooting process.

Be patient and consistent. Technical glitches are frustrating, but usually, a little bit of troubleshooting will solve the problem.