Week old chick walking on hocks

[Abshans]

Hello! I have a blue Orpington chick that was mail delivered a week ago. Everything was fine until she was like 5 days old when we noticed she was reluctant to walk on her feet and would mostly walk on her hocks with her wings flapping. I reviewed some discussions on here and it seems to sound like vitamin b2 deficiency so we did start her on a b complex yesterday- about 1 day after symptoms started. I am wondering if anyone has had similar experience with such a young chick? Today is the second day we have her the b complex and truly don’t see much improvement. I am not sure how long it might take. She can and does stand, but is very wobbly and doesn’t last long. She is eating and drinking