Avast premier shields turning themselves off

[REDACTED]

Hi, i have been using avast premier for the past two years with no issues but for the last two days the shields have begun to turn themselves off and if i do turn them back on and start a full system scan, after 30 minutes or so during the scan they turn off again, has this ever happened to anyone, if yes how doni fix it. Any help would be apprecited

[Eddy]

What OS/SP ?
What exact version of avast ?
Any other security (related) software installed ? (or was there)

[REDACTED]

Sorry for the late reply, Windows 10 version 1511 build 10586.218  and i also have malwarebytes installed, avast version 12.3.2279 build 12.3.3149.0

[Eddy]

Update avast to the latest version.