We have a Honda Civic 2009 two door. You can only put a key in the driver’s side door or use that clicker to open it. About two weeks ago we could no longer open the door due to the key only going in halfway. If the door is locked only the clicker can be used. so if the battery goes on that and the door is locked, well, that is not good. My spouse took the car to the Honda dealership and they wanted to replace the whole lock system. Of course the car just went over 36,000 miles so the warranty is out. My question is: Has anyone ever have this happen to them? My aunt said to just try lubricant in the lock. Thank you for any info anyone may have 
I’m Thinking Locksmith On This One.
Dealer mechanics or most auto mechanics are equipped to replace the troublesome components rather than repair them.
An established locksmith, especially one who does automotive work, perhaps could evaluate the situation and give you some options/estimates on repairing the lock.
I wonder if somebody (thief, vandal, child) put something in the key hole or maybe a tumbler or spring malfunctioned. Who knows ?
I’d make some calls, locally, and see if a particular smith sounds user friendly. I’d ask if anything close to a free estimate exists.
CSA
P.S. You could try a lock lubricant as suggested by your aunt. I have seen this work, although usually on older cars or cars subjected to lots of salt or locks that have the little spring loaded key hole flap stuck open.