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Since Thursday last week I have not been receiving text messages from certain numbers when connected to Wifi on my Samsung Galaxy S5 Neo. It's only from certain numbers - The rest work fine. This started last week - As soon as I switch WIFI off the messages come through instantly - I have updated my phone's software but this hasn't fixed the problem. Has anyone else experienced an issue like this?
This may be due to having advanced messaging turned on for chat in your phone message settings. If you have the feature enabled try turning this off, the sender may also be using chat. However, you should still be able to receive the messages over WiFi, that leaves it a mystery, hopefully soon solved.
See here: Messaging Features