I had the same issue that the key sometimes wouldn't work.I also recently changed the battery so that’s not the issue.
Well not so fast. Did the issue arise after you changed the battery ? if not then change the battery again and keep fingers off the battery terminals and use a cotton but and iso alcohol to clean the key contacts. It's not that unusual for new batteries to be undervoltage or low on capacity. Sometime they are old stock. Worth a try before going on to more costly solutions.Does anyone else have to press the lock button multiple times and wait for it to lock. Sometimes it works perfectly and sometimes it doesn’t. I also recently changed the battery so that’s not the issue.