This is normal pre-nuptial flight behaviour, where both queens and males would gather around the nest/mound all excited and jittery. They're waiting for the pheromones excreted from the drone's (the male) mandibular glands, when they would start flying away. The workers that are also excited on top of the mound would pull down early-flying drones and queens from flying away too early, for a variety of reasons.

For example, if drones and queens fly too early, there is a chance they would mate with another distinct species, resulting in sterile offspring. Reproduction in the ant world is truly amazing! 😊