Hi manaledi,
Apologies for the delayed response. I request you to check the system in Safe Mode. To go to ‘Safe Mode’ restart the system and at the Dell logo tap the F8 key every two seconds. In the ‘Advanced Boot options’ window using arrow keys, select ‘Safe Mode with Networking’ and hit enter. Once the system boots to the desktop check the network connections. In case the system works fine in Safe Mode with Networking, I suspect the issue may be with the antivirus software. Please uninstall the antivirus software and check if it works fine in normal mode.
Please revert with the status.