My 13 inch 2017, 4 thunderbolt,3 ports, N key does not function

The "N" key is the most common key to fail on the 2017 model. The best you can do is to try cleaning the keyboard with compressed air using the instructions in this Apple article making sure to keep the can of compressed air completely upright, otherwise you will damage the laptop with cold wet propellant:

How to clean the keyboard of your MacBook or MacBook Pro - Apple Support

I doubt compressed air will solve the problem since it is the "N" which is not working. More than likely the key switch has failed which is the reason Apple had the free Keyboard repair program (no expired). Most of the broken "N" keys involve a defective key switch.....there is nothing you can do to fix a defective key switch other than having the entire Top Case/Keyboard Assembly replaced). However, these butterfly keys are also very susceptible to small bits of dirt or crumbs jamming up the butterfly mechanism since there is very little clearance. So there are two different issues with these butterfly keyboards even though both issues have the same behavior from an end user perspective.

I do NOT recommend attempting to remove the key cap as others have suggested because you are more likely going to damage the keyboard. The key cap is very thin & very fragile where you can actually crack the key cap. Plus it is very easy to damage the clips on the key cap, or the studs (protrusions) on the butterfly mechanism. While it may be possible to get a replacement key cap (there are lots of variations in the font and the coloring ....all black, but there are slight differences which stand out if one key is different), but it is impossible to replace a broken butterfly mechanism if a stud/protrusion if broken. Usually the compressed air will move the crumb out of the way if it is a crumb causing the problem.

If you have never had the Battery replaced, then see if the Battery Condition is showing "Service Recommended". If so, then take the laptop to Apple to have the Battery replaced. The entire Top Case Assembly will be replaced so you will also get a brand new keyboard, but for the lower repair cost of a battery repair. Do not mention the key issue or Apple may want to charge you for the much more expensive Keyboard repair. The best time to see a "Service Recommended" condition is when the battery charge is less than 10%.

Hope you can fix it. I believe that Mac was one of those with a "butterfly" key mechanism. Apple introduced the butterfly keyboard on the 12" Retina MacBooks (which were too thin for regular keyboards), but it soon spread to other Mac laptops. Then it turned out that if dirt gets lodged in the keys, it's hard to get it out.

There was once a keyboard service program for Mac laptops with this type of keyboard, but the deadline to take advantage of it has expired.

Keyboard Service Program for MacBook, MacBook Air, and MacBook Pro - Apple Support

Here's a CNET article with suggestions of how to get debris out of a keyboard – and how not to get it out. They warn against spraying liquid of any kind into a keyboard – and say that "If you've got a butterfly keyboard, don't ruthlessly pry the keys off because it can cause damage to the butterfly clip mounts."

https://www.cnet.com/tech/computing/sticky-key-on-your-macbook-keyboard-heres-how-to-fix-it/

MDU32 Said:

"My 13 inch 2017, 4 thunderbolt,3 ports, N key does not function. Laptop has been updated"

Troubleshooting a Mac Key Not Responding:

Reset the SMC and your NVRAM: Sometimes when changes are made to the system(i.e. Updates), system configurations (i.e. for keys) become manipulated, technically. So, reset the SMC and NVRAM. Try performing each thrice, using an External Keyboard. It may take sometime, being certain you have the time to perform these resets. (Applies to Intel-Based Macs Only).

MDU32 wrote:

My 13 inch 2017, 4 thunderbolt,3 ports, N key does not function. Laptop has been updated

To correct the key manually.