One character key stopped working

Our users will need to know the specific Laptop model to correctly assist in troubleshooting.

If one key on your keyboard has stopped working, several troubleshooting steps can be taken. First, try restarting your computer or unplugging and plugging the keyboard back in. If that doesn't work, inspect the keyboard for physical obstructions like dust or debris. You can also try using an external keyboard to see if the issue is specific to the keyboard itself. 
Here's a more detailed breakdown of troubleshooting steps:
1. Check for Physical Issues:
Dust and Debris: Use compressed air to blow out any dust or debris under the keys. 
Jammed Key: If the key feels stuck or unresponsive, gently try to dislodge any obstructions. 
Cable Issues: If you have a wired keyboard, make sure the cable is securely plugged in. 

To receive assistance from Dell chat support, they need to verify the warranty status and ownership. Then you must troubleshoot with them.  Click the "Get Help Now" icon on the right to start a live chat session. If already out of warranty, click here for the Dell out of warranty offering.

Well I will suggest you to update the keyboard driver if it outdated so check that as well and also try to connect different keyboard in your laptop top and check the problem is still happening or not.