Outlook Email Access Troubleshooting

I am currently facing a significant issue with my Outlook. I am unable to send emails and this issue is consistent across all devices; webmail and other devices are also affected. After composing and clicking send, the email sits in the drafts box and does not actually send.

I need a professional who can help troubleshoot and rectify this issue. Ideally, the freelancer should have strong skills in IT support, specifically with Microsoft Outlook. A good understanding of email server issues would also be advantageous.