Thank you for replying. I did use an external keyboard and the CTRL keys work fine. Do you happen to know a way that doesn't involve replacing anything?

Try a USB keyboard, or the on-screen keyboard.  If those show correct function of the CTRL key, you will need to replace the palmrest assembly (the keyboard is not separately replaceable on this model).

https://www.parts-people.com/index.php?action=category&id=143&subid=1436&refine=keyboard

If it were one or the other key, but not both it could be that one has something jammed under it but with both, that's not the case.  If that key is not working on either side, the keyboard-palmrest assembly needs to be replaced.

It's not an easy process -- the service manual has the details:

https://www.dell.com/support/home/en-us/product-support/product/xps-13-9300-laptop/docs

I appreciate your help. 

I have the same issue.

Both ctrl keys are not working anymore on my XPS 9300. 

I checked on the on screen keyboard and they are not working there as well.

On the external keyboard ctrl keys work fine.

This is very weird.

Is this an hardware or software (driver) problem?

Any ideas from anyone?

Got the same issue on both keys, but time ago I've discovered that pressing repeatedly both buttons sequentially turned out to make them work but just temporarily. Was looking if progress had been made somehow as it's pretty cumbersome to have this issue whenever I'm not using the external keyboard (that works fine obviously).

Wish to hear if there is any interest on DELL's side to fix this on such expensive products Thanks.

Yet another person with the same issue. I was told it is not worth replacing it all to fix. Not great. On mine if I try two ctrl keys and V I paste 5v - I think this is a driver issue.

Hello, I have the exact same issue. Both CTRL keys only work once in a while, after pressing them multiple times…. What are the solutions for this ?

@NotLeandre​ unfortunately the only solution seems to be the replacement of the keyboard component. But honestly, on a so cheap device (I'm ironic, obviously) having such a fault from a device produced by DELL (which should be warranty of quality and reliability) is frustrating on such premium and costly devices. Long live China!?!

I have the exact same issue. Following this thread for the solution as my laptop doesn't have warranty anymore.