Galaxy note pro 12.2 wifi cant connect. Keeps searching but cant see any signal from any network.

[AC Question]

My pro 12.2 used work fine - no problems, then suddenly yesterday i tried to connect at home or now office wifi (all other devices can connect incl my samsung phone) and it keeps searching but can not see any network with a signal. Now, my samsung phone can see many other networks with ok signals but the pro 12.2 keeps searching and even though it sees my home network its as if it has no signal and 'searching' never ends.

Please help! I have not updated, have not downloaded anything it just happened. I cleared cache but dont want to wipe. Please help.