Problems with Internet via home WiFi, mobile data and other WiFis work fine I'm having various problems with two Android phones in my home WiFi: from time to time, the phones


can't connect to the WiFi at all (despite stored credentials) -- happens only rarely
can connect, but get no Internet access via the WiFi (e.g. right now I'm getting DNS_PROBE_FINISHED_NO_INTERNET, but the another time it might be a different one) -- happens more often (say once every two weeks)
can connect and get Internet access, but with a big lag (DNS lookups and/or establishing connections is very slow, once connected the bandwidth is fine) -- happens always


At the same time, the phones work fine with mobile data and other WiFis. Similarly, the home WiFi works well with our laptops. It seems that there is something problematic in the specific combination of these specific phones and that specific WiFi.

Workarounds that I've tried and that sometimes (but not always) work:


Disconnecting and reconnecting to the WiFi
Disabling and re-enabling the WiFi on the phones
Rebooting the phone
Removing the stored credentials for the WiFi from the phones
Resetting the WiFi access point


One of the phones is an Lenovo C2 (K10a40) running Android 6.0, the other one is a Samsung S4 mini Gt-i9195 also running Android 6.0.

The WiFi access point is a TP-Link TL-WR841N/ND v9 running OpenWrt/LEDE Reboot 17.01.4. The WiFi is using WPA2 PSK encryption and automatic channel selection.

I've checked other similar threads on android.SE, but none of them suggest anything that I haven't already tried.

What are possible reasons and solutions for these problems?
Please check what type of wifi your router broadcasts. If it broadcasts both 2.5Ghz and 5Ghz your phone may discover the 5Ghz network, try to connect to it but then has no "power" to stay on that type of network and falls. So make sure your device is connecting to the 2.5Ghz network.