Are your rabbits fixed?
Introducing rabbits can be a real pain in the butt. After Bilal was fixed, I had to wait several weeks just to get them near eachother. I started by placing Bilal's smaller cage next to Walter's cage -- which would eventually house the two of them. Once a day I would introduce them on neutral ground, and keep them together as long as possible until fur started flying (there was never any blood or screams, but Walter would bite a chunk of Bilal's fur out and chase him aggressively.) Every day they tolerated each other more and for longer periods of time. Eventually, actually on Christmas, they hung out harmoniously for hours, but still fought on marked territory (if one entered the other's cage). A week later I took them to my friend's house in Cumberland, and they fought the drive up (or would have if they had been in the same cage), were allowed to run around the guest room all weekend, and came home best friends, able to be housed together. On occasion they get too frisky while playing and Walter will bite a chunk of Bilal's fur out, but with intervention they go back to normal right away. They are inseparable and play together constantly.
My point is, it will take awhile, and the process can't even begin until a couple weeks after fixing. The two most helpful things in my experience were putting the cages right next to each other, and car rides together (NOT both cramped in the same carrier, which is recipe for disaster.) Just some ideas...