It’s quite possible they are active when your not around/sleeping. Rabbits are very active late at night (around 12-3) and early am (6-9) or so…Also, are they spay/neutered? Altered buns tend to be calmer as they don’t have raging horomones to deal with ( a GOOD thing
).
Rabbits love to explore and practice running around. Rearrange things in their cage/pen and the area of the house they are allowed out into. If it’s different they’ll HAVE to check it all out and run around. This keeps them interested and active.
Offer different toys twice a week. You don’t need to break the bank, there are many toys you can find around the house or make yourself! Check the ‘toy test’ forum section on this site for ideas. To name a few-phone books and diggy boxes!!
Do you rabbits have ‘rationed pellets’ (ie. they aren’t free fed)? If they get excited about pellets you can scatter them all over the cage/pen so they have to move around and forage for their pellets rather then sitting and eating them.
You can also try playing a radio or Tv for them to offer more stimulation.
Hope these suggestions help and I’m sure other members will have more for you! 