The current understanding of rabbit reproductive biology is that does are "induced ovulators," meaning that the attentions of the buck result in ovulation. They do have cyclic phases when they are more receptive - this is reflected in the color of their vent, with dark pink indicating more receptive than light pink - but as far as we know, rabbits don't go into heat like some other mammals. Some researchers say ovulation happens during the act of mating, others say it happens within 12-24 hours, but it is mostly agreed that mating triggers ovulation. This is probably why it is sometimes possible to facilitate a mating by holding and lifting the doe for the buck even when she's not really "in the mood."
Normal healthy bucks should be interested at
all times (unless temperatures are extremely hot); most of my bucks don't care if a female is interested, mature, or even female
.
It may actually be that they are "bored with each other," so to speak. One study found that while having a buck present increased does' receptivity, prolonged visual and tactile contact with bucks decreased it:
"In conclusion results from this study indicated that the presence of the male improved the sexual receptivity of the doe. However prolonged visual and/or tactile contacts between the opposite *** appeared to be detrimental to the breeding efficiency and overall productivity of the doe."
https://www.researchgate.net/public...tivity_and_kindling_performance_of_rabbit_doe
One of the tricks that breeders use to get does interested is to switch the cages of the buck and doe for a day or two. That way she is exposed to his smell, but not badgered by him. You might try that. I usually put the rabbits back in their own cages when it's time to breed them, always taking the doe to the buck in his cage.
Honestly, your rabbits are giving you such problems that I might be inclined to try some new ones if that is an option. Females can have "off days;" I give them about three days of visits to the buck's cage, and that usually does the trick. You will occasionally find that a doe just doesn't like a certain buck, but will happily lift for a different buck, but it shouldn't be the case with
all of your does.
Your buck, though, sounds too finicky for his purpose in life - unless he has some outstanding characteristic that you desperately want in the kits, I'd be looking for a replacement.