My son is 2 yr 10 months old & he is not properly talking. He speaks only single words. Can you suggest me what should I do?

Hi! My 2 yo son is not yet talking properly. We had him assessed by a devt pedia when he was 22mos and was initially diagnosed with GDD cannot rule out ASD. We want to give him all the help we can so we enrolled him in a therapy center for OT and SLP. He's been there for 17 sessions now and He is not yet talking butbwe saw great progress in his behavior and started babling words.