Push notifications not working on WiFi

[reResd]

I have an Xperia E4 with Kitkat OS.
When my phone is connected to WiFi, push notifications for Chrome, Snapchat, and Twitter do not come through.
All apps are up to date, and when I switch to mobile internet my phone is flooded with notifications again.

I seldom use mobile data because of the usage charges.
Please help

[CameronT]

Hi @reResd,

Go to Settings > Wifi > Options > Advanced. Is "Keep Wi-Fi on during sleep" set to "Always"?

[reResd]

Yes, my WiFi during sleep is "always" on. As said, mobile data gives me notifications, but WiFi doesn't, eve when I'm using my phone.

[CameronT · Accepted solution]

@reResd, is your modem/router set to ipv4 or ipv6? I believe it will not work if it is ipv6.

[reResd]

Just did some researching and apparently push notifications do not work on IPv4. 

Just swapped to IPv6 6to4 and it works like a charm, THANK YOU!

[CameronT]

That's great @reResd, glad it's working for you