Device has not been synchronized for more than 30 days

i’m using avast business basic now, i found some pc will show "device not synchronized " after few week of installation and it happen again and again. sometime re-install will solve this problem but not all the while. One of the pc had this message occur around 3-4 time.

OS used: win7 64Bit
other application installed, 360 total security (without anti-virus). i using same version of this software and avast product at my win10 laptop, i got no this problem at all.

If let said 360 really accidentally delete some file and cause this problem, is it possible let me know what file i should looking for ? possible to reconnect this device to cloud server?

At the moment i waiting reply, i had another 2 pc having same error
This time no other antivirus / anti spyware software installed

Contact business support: https://support.business.avast.com