Try to fix the google account settings on my avast site.
I think these are right it is backing up fine, I can restore from and older device on my account to my current android phone with the avast app, but not from the my avast account. This works fine for me but not for trying to do it remotely online for my in-laws new phone.
Just a hint: "my avast site" = https://my.avast.com
Yes, that is where I am trying from and even with different accounts and different devices I cannot contact the devices I get the "We are unable to connect to your device" message. As previously stated I can restore from the avast android app but not my avast which is what I need to do.
I would walk the through the process of them doing it from their new phone but last time they tried to do something they somehow lost a heap of photos so they are hesitant to do anything with it.