Phpmyadmin iin docker (linux)

Hi.
If I install mysql and phpmyadmin in docker. Does anyone know how I can access the phpmyadmin to manage the databases?
Thank you

mysql

docker run -d --name mysql --restart=always -p 3306:3306 -v /home/sysop/docker/containers/mysql:/var/lib/mysql -e MYSQL_ROOT_HOST=172.17.0.21 -e MYSQL_ROOT_PASSWORD=stinkycemo mysql/mysql-server

phpmyadmin

docker create --name myadmin --restart=always --link mysql:db -p 8383:80 phpmyadmin/phpmyadmin

I found how to install phpmyadmin for docker and install it with the following command line

docker run  --name db21 -d -e PMA_HOST=db21.cluster.us-west-2.rds.aamazoaws.com -p 8021:80 phpmyadmin/phpmyadmin

when I run phpmyadmin from a browser it returns the following errors.

El servidor MySQL no autorizó su acceso
mysqli::real_connect(): php_network_getaddresses: getaddrinfo failed: Name or service not known

Can you think of how to fix it? I would think it is a permitting problem. But I don’t know how to fix it. thanks