can't log in with my iPhone

I normally don't log off and just stay logged on with my Mac, iPad and iPhone.
For some reason last week all 3 devices were logged off. So I simply logged back on.
I was successful with the mac and pad but it won't log in on the phone.

I've killed all the apps and turned the phone off and then on several times and still unsuccesful.
I'm not using any type of app for this forum. I just have home page saved as an icon.

It's really frustrating since I get notification on the phone and can't reply.

Any one have any suggestions.

Did the cookie acceptance setting get changed. Mine used to mysteriously change to no longer accept cookies.

U Da Man. That was it. Somehow it was set to "accept cookies" ... "Never"
Don't know how it did that, but thank you.