Its ok. Keep talking and doing actions with baby. Some babies start responding late. But do try to call the baby with his/her name and try to interact. The child must respond with a smile or laughter or anything. It doesn't have to be a pointing or hand action etc.

Keep talking to the Baby... why don't you buy touch and feel books, sounds books.. it will help.. play Rhymes and sing along.. you make actions and show.. baby will learn, it will take time..do not worry..