Auto Mate keyless entry

I dont expect to get a solution for this since its not really nissan versa related but ill give it a try
I have one of these's Automate Keyless Entry
My problem is that about a month ago my back doors stopped working meaning it wont lock/unlock and about a week ago i changed the battery on the remote and now none of the doors wants to lock/unlock my theory is that i need to reprogram or reconnect the remote to the car. But i dont know how the website which the keyless entry systems comes from is terrible and i dont know how to contact them. I dont really know how the system works because i bought my versa used and it came with it. Anyone have any ideas? thanks sorry for my bad English