I put a dummy google account for my Samsung S8+ after the factory reset(something like email@example.com) in order to let the service use it and protect my data(factory reset). So now they returned the phone to me and I did a factory reset again to login with my google account now i getting the error:
"This device was reset, to continue to sign in with a google account that was previously synced on this device"
I actually have a 'google account that was previously synced on this device' but not the last one ! So basically I repaired my phone and now i can throw it away ! Please update the algorithm to work also with previous google accounts or I will hate google for the value of my phone - Remove google ads and switch to an iphone not much better with icloud but this would not happen.