I have exactly the same problem with connection.
Till 12:00 CEST or so it worked all normally.
Then Im suddenly disconnected.
I try to log off and restart the app nothing...
I try rebooting the phone...nothing...

Then I switch to Mitakuuluu to see if Im banned (again *sigh*) but this is also not working the app either crashes or tells me no route to verify registration via sms..thats a Mitakuuluu problem..and I currently have no time for investigating...

So I install the devil..the android app.. to understand whats (h)aAPPening - PUN! haha - so funny I know!
and.... It works!?!!! No ban. I can normally chat and edit contacts etc.

So back to Whatsup...and here I can't now not even re-register, clicking on connect does nothing and I can only see old chats.

Any Ideas? I preferr the native clients over the android they are smooth, nicer, less "hungry", mor intuitive...just better