How do I make my dumplings juicy again?

I tried the viral dumpling lasagna today. I added minced chicken,cabbage,spring onion, ginger garlic paste, extra chopped garlic, onions, soy sauce, vinegar, salt and pepper. I layered the filling and dumpling sheets in a cake tin and steamed it for 1 hour but it wasn't fully cooked through so I popped it in the oven for 5 mins.

then I topped it off with chilli oil and when I took my first bite it was supeeeer dry. tasted very similar to a dry kebab. I ate halfway through it but its too dry to finish. how do I make it juicy again 😭 could someone help me out real quick