Authorisation Problem WLAN/connectet, but no Internet

I have Sony XZ1 and Sony XA1, both with Avast mobile internet security. Since 4-6 Weeks i have several Problems that the WIFI-Connection says “authorisation error” or is connected to my Router and says “Router has not Internet”. After reboot of the Router the problem seemed solved, but returned an hour later again.

Same Problem at home and at work, i thought it was a Sony Problem, but my wifes Samsung A5 has the same Problem.

After deinstall of the Avast-Software from my phone, the WLAN-Connection is stable. In the last weeks very often a message appeared “mobile Security does not work properly, Wait/retry”, Other software no problems.
After Deinstall of Avast on the Phone now Facebook shows this message!

Please help me.
Andoid’s are the actual Versions, all Updates installed. Android 7.0, Kernel 4.4.15 Model: G3121 (1 of 3 Devices)

Hi, how often did you use the “Wi-Fi scan”? It is the only feature which could theoretically influence the router.

However, from your description of the problem it rather seems as service unavailability/failure with your Internet provider - have you contacted them regarding the router issue? If you did, what was the outcome?

Regarding the other problem, it might be a system problem (when AMS is uninstalled, it can hardly show any messages). I can recommend you to check your device Settings, find the “Stamina Mode” and tick what apps you do not want to be killed when running in the background.