Remote doesn't work most of the time. Put new battery in but no luck. on 2006 Suzuki Grand Vitara

It used to be mostly when the car had sat in the rain but then it started happening almost every time I tried to use it. I've had some issues with the interior lights too. I'm concerned it's not the remote itself but something in the car.

Asked by for the 2006 Suzuki Grand Vitara