I just reformatted and reinstalled everything on my pc, but every few minutes or after a boot-time scan, I get an error saying that my device was removed from my account, please relog. Why does this keep happening? Any help appreciated.
Had similar issue.
Went to My Devices and selected a Device clicked on settings and ‘deleted’ the device. Deleted all secured devices. Disconnected from Avast Account via Settings/General.
Then Reconnected and secured Device.
Issue disappeared.
This may or may not help in your particular situation 
Will try it now and update it
Did not work, though I had to remove devices from website and not actual application. Anyone else have any ideas?
You need to do it through the actual application… else it won’t work.
As I stated, the process is done by going to ‘My Devices’ within the Program (GUI)
For some reason when there is only 1 device left it wont let me do it through the gui, any ideas? or a step by step?
Avast>Settings>Disconnect (from avast account) if that is the PC it’s registered too…
Will try
What is the one device left ?
If it isn’t for that particular avast installation, then I don’t think it would be able to display anything as that device isn’t connected.
Check the avastUI > Settings > General - Avast! Account Status.
Disconnected through the ui, then reconnected, waiting so see if it is fixed
I’d suggest a reboot now to eliminate any sync issues.
Appreciate the help, will sign out again, update my graphics, restart, and sign in, will update
So far, so good, will keep updated