I had assumed problem of connectivity with my Bluetooth and my WiFi on the phone.
With Bluetooth when I tried to connect to a known device they start connecting than nothing happened, for the WiFi I had exactly the same problem when I was going to my mother’s house with her WiFi registered on my phone. The two issues were solved individually by just restarting the mobile phone. Hope this help someone.
The version is 0.22 now but it was 0.20 when I wrote the post. My device was Xiaomi Mi A2 and now it’s Xiaomi Mi 6X. I still have this problem sometime.