Thanks @Tony! I was going to follow your advice, and then suddenly found out that my router has 2 wireless networks 2.4GHz and 5GHz, so I was using different password. Now it's connected, thank you...

Hi @Tony , has this fixed version been released already? Kasa app Version 2.17 seems to be without fix

Model: HS103P2 Having same issue - setup stuck on connecting to wifi step. Reset plug/airplane mode doesn't help