Cannot find any of my location beacons in the Estimote App

We have 300 location beacons and turned off enabled in the iBeacon settings while storing them. Now we are ready to deploy these the Estimote app cannot detect most of these beacons. They are only 3 months old so battery should not be a problem.
I have logged in and out of the Estimote App. I have changed the settings in the Estimote portal and I have tried different phones and nothing works.
Can anyone help on this?
Thanks, Sarah

It seems that maybe the Estimote App was down as its all come up now, however the App keeps crashing, so perhaps some time needs to be given to updating this bug.