problem restore wordpress site in local

Good evening, I have a problem with wordpress.

I had to migrate a site with database because it was attacked and I saved it locally via MAMP, through the various guides I did the complete process that is:

backup database;
install locally a new clean wordpress installation;
import databases;
insert old site folders into the new copy.

So far so good, I changed the absolute address in the database and I put the one where MAMP is installed, I created a new account (via database).

I see the site but when I go to login at:

xxx / wp-admin

gives me the login form and first came out of an error screen: “You do not have permission to access”, now instead I return to the home site but I can not enter the dashboard.

How can I do?

Thanks so much