you can try picking him up every day for a couple of minutes each time or a few seconds if he starts getting panicky, and then every time you put him back down, give him a reward he loves.
You just have to remember, some bunnies will probably never like being picked up, some bunnies will take a long time to get used to it, and some bunnies won't mind it. It is natural for Bunnies to not like being picked up, due to their natural flight instincts of predators lifting them up.
My Bun is one of those Buns that do not like being picked up. Even as a little baby, she didn't like being picked up.
She is absolutely sweet with her snuggles and being petted and massaged, but she just has never liked being picked up. So I just don't pick her up unless it's absolutely nessarcary. I only ever give her pets and massages and treats from my hand.
I do understand your fear of breaking the bond, as I had the same fear with my Bun, as I was picking her up for a few minutes each day and giving a reward for about a couple of months, but she didn't change. So I decided that I would just give her lots of pets and massages and interactions from me without picking her up.
So I suggest that if nothing works or helps, just keep up the petting and massages, because some Buns just won't like being picked up at all.
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