Helloo, my whites tree frog Herbert has seemed to stopped croaking.

I have had him just about a year now, he has a large set up with heat mat & lamp, lots of trees & branches and a generous pool area
& I feed him 3-4 crickets everyday 3 days, dusted alternativly, but he is not hand fed he catches his own food.

He is a very small tree frog ( the smallest out of the bunch at the shop where he was bought ) but does not appear to have grown very much over the past year.
He was very active when we first got him for the first 5 months & croacked all the time, sometimes in the day & at night time, but over the past 4 months since we have moved house he seems to have stopped croacking all together & we very rarely see him active & he sleeps a lot. Is there certain seasons where wtf's croak more and are less active? Is it normal for him to be doing this?

I have checked him for any marks & injuries and all seems to be well, apart from the fact he hasnt grown much. I am quite concerned about him & want to give him the best life i possibly can, any advice would be great