The sending address is likely spoofed. If you block it, you'll likely get the same message from another address. Paypal has two factor authorization, which you should be using. Logon to your Paypal account, and hit the little "gear" button on the upper right. Select security, then two factor authorization. Once you turn it on, anyone who wants to access your Paypal account would not only need your password, they would also need your cell phone. The downside is that you also will always need your cellphone to use Paypal.