Started getting connect to acs failed overnight

[Gary139]

The last couple of mornings I can't connect to the internet. 
looking at the logs the lease renewal stops at about 2am then no lease renewal message received, then dhcp lease expired about 3am, then received a valid dhcp lease from server, but then after that it sends ntp requests which fail with connect to acs failed, could not resolve host.

Pressing the reset button seemed to fix it yesterday but hasn't this morning..
also noticed my data usage goes up a few hundred gb as well.