Had my Lancer about a week. The keyless entry stopped working last night

I locked the car and when I came out after dinner, I couldn't open the doors. Used the key to do so and the alarm went off. Started car with the key and alarm silenced. Replaced battery in keyfob, still not working. Red light is blining when I press a button, but nothing happens - except the red light on the keyfob does come on.

 

Update:

Had my car in for recall service(s) and mentioned my keyfob issue. At first the service guy said you need two keys. When I said I only have one, the look on his face was as if he was saying "sorry for your luck, but nope..."

Anyways they took the car back into the garage and tried a few things. Whatever they did got the fob working again. I was in touch with the dealership I bought the car from and they have since requested and are getting the 2nd key for the car. So, I'll be set in the future. I'm sure this is something I could have done, seeing as the instructions are in the manual...