Amazon has a strict tool that they use that helps prevent hacking attempts from large databases of passwords collected from hacking groups and other tools.
The way their tool works is by blocking the login attempts after a certain number of attempts.
Easync will only try your login a few times and if we get a the failed attempts we will stop. This is to keep Amazon from thinking that we are doing exactly what I stated above.
We don't want Amazon to think that a hacking group or something like that is trying to access your account.
You can also wait a few hours and try again because Amazon knows that eventually you will try to login to your account authentically. So that period of waiting can do some good also.