A few more words would help massively to understand your actual question.
That said, ACS/ auto should never be used. There is no smart algorithm behind auto, it just sets the first legal channel for your environment (so effectively ch1 or ch36) - regardless of your environment or if other channels would be better or completely free. Always select a channel manually, based on your surrounding.
EDIT: As this post seems to be referred to quite regularly.
Modern drivers (ath10k, ath11k, mt76) have gotten a little smarter in the mean time and can use ACS in a smarter way, but it's still preferred (and can avoid real problems) to choose a channel manually (especially with DFS in mind).