beautiful baby !
Birds need lots of social time, it could be increasing interactions and out of cage time will help.
I use cages for safety when im gone, for sleeping, and when things are to hectic to keep an eye on them . The rest I have them out , and try to include them or set them up to hang out near me.
You have a nice cage and I see fun toys. But you can also turn the outside of their cage as a home base hang out play stand. By putting perches on the outside of the cage sides and top and a few toys and things to chew. Don't let that valuable space go to waste.
Young just weaned burds might still be learning food. Make sure food us always available and they are eating well.
Try whistles and phrases , if they learn those its easier to listen too than other vocals.
Have a phrase or whistle that you use as a flock call. Burds like to sound off and know you are within hearing. When you step out of sight give your flock call whistle or phrase. When they give an exploration call answer with yours. Be consistent.
Some burds like a little ritual routine in the morning and before bedtime. Mine all get a good morning and kisses blown at them when I get up but before their breakfast. At night a couple really like cuddling and sweet talking before I put them to bed. If I forget they get realy fussy and anxious