Invalid receiver business id/email address message in Usermanager

Can anyone tell me why i’m receiving this message in payments log inside user-manager? Before was working and since no know paypal does not work anymore. Any help will be highly apreciated.

“Invalid receiver business id/email address”

Using 6.34rc27

Thanks in advance.

After intensive testing and paypal sandbox setup discovered secure response does not work for me, probably need config. And userman customer public host must be left blank to work. Make public because can be useful for someone.