Has the battery been replaced before? If not, it may be due (probably three years since the car was made). You should be able to change it yourself for a couple of bucks although I've only done that on our Lexus and Honda. Not sure how user-serviceable the Subaru fobs are.

 

No, I haven't replaced it before. I'll have to look into how easy it is to do myself. I still find it odd that it's unlocking and locking just fine, makes me think that something else is causing the problem.

 

This is just one reason I want nothing to do with vehicles with push button start.There are those who have had this issue and those who will have this issue if they keep the car long enough.Another reason is that your key fob is constantly sending a signal in an attempt to communicate with the car.Thieves now days have a machine that can receive,store and reproduce that signal and all they have to do is get within range of the fob.Once they have that signal they can drive away with your car like they owned it and the car won't know any better.So the only permanent fix is to trade it in on a car with a real key.Just one more reason why I will be holding on to my '16 premium,with a real key,for the foreseeable future.

 

Even the "real key" cars have this problem. The '02 Lexus we replaced with the '18 Crosstrek would not start unless the electronic part of the key was attached to the actual metal key. We learned this when the plastic part of the key containing the electronics broke off (it eventually happened to both of them).

 

If you have a second fob, try it.

 

I am having the same issue and I have attempted using two different key fobs. I can get out of my car lock it, unlock, get back in and it starts. Did you end up changing the batteries and it worked?