I got this phone some months back from a trusted dealer of UK used phones. Everything works and the phone looks and works effectively like a brand new phone.
However, I noticed that certain apps I download don't work on the phone. Like yahoomail and Facebook messenger. I can't even access yahoomail from the browser. The response I keep getting is "network connection down " I've tried all sorts including using wifi but I still get that same response. It appears like something in the phone has been programmed not to give me access to both yahoomail and Facebook messenger.

Please what is the cause and solution?

What phone brand / model is it?

Also, are you using this phone over wi-fi or with a SIM card?

MarkWayne89:
What phone brand / model is it?

Also, are you using this phone over wi-fi or with a SIM card?

It's a HTC m8. I'm using it with a sim card

Follow this steps

1-try to reset the phone by using the factory reset on the phone when you click on the setting and if this method doesn't works

2_-give it to a software engineer near you to help reset the phone by flashing it or

3-check my signature for more details

First, check if your phone's IMEI hasn't been blacklisted in the meantime. You can check it here http://imeipro.info/

And if the phone's IMEI is clean, then you can do a factory reset to restore your phone's initial settings and default apps.