Botrytis bud rot.
Cut off any affected and check stems to see if I see any fungal growth on it or any plant nearby, the buds develop resin /trichomes and Well fungal spores are very easily “captured “ by the buds. It’s why usually if u see this , there is a bad plant any plant with this fungal element and or u have a caterpillar eating and pooing inside the bud causing bud mold/ rot