Does he bite gently first? If you ignore the polite "no thank you," he has to get more assertive.
Are you taking him somewhere he doesn't want to go? If he knows that, he might refuse.
How long have you had him? Have you built up trust with him so that he wants to step up/be with you?
Have you done any training with him where stepping up = reward?
Have you tried alternatives to getting him where you want him? If Bumble won't step up I just leave the room - she never wants to be away from me so she flies over and lands on me before I can make it out. She does frequently land on my head and sometimes doesn't want to come down LOL but at least she's closer.
Sometimes a bird just doesn’t want to step up! With my Quaker parrot, I have learned to pay careful attention to his eyes and his body language to see if he’s in a biting mood. If I have to move him when looks ready to bite, I wrap a towel around my arm ( he steps up onto my arm, rather than my hand) so that he doesn’t hurt me. You could also try teaching him to step
onto a stick or perch so that he doesn’t bite your hand.