Yes, people tried to convince me for a long time too. I had a teacher in college that tried to convince me, but what I had been taught was too ingrained. God had to remove it LAYER BY LAYER. There have been many Christians who have had the same experience. Judge not before the time. Let God decide who are his. You don't know what a person will hold in five, ten, fifteen years.
My transition from NOSAS to OSAS was a long, gradual journey. But the whole time, I knew that I had been justified by grace, and Christ was keeping me by Grace. I was not depending on works to save me in any way.