Can you skin become immune to prescribed acne medication?

I've had acne since I was 14 years old. I first when to the dermatologist when I was 16 the doctor prescribed retinol-A and topical gel. I tried for a year and it didn't do sh!t. Eight years later I went to a different dermatologist. She prescribed me duac gel and differin gel. Within two months my face was so clear I didn't even need make up. Two years later both medications are losing their pizzaz. My face is covered with acne. Now I have a healthy diet, exercise and I drink lots of water.