Can't connect with new user created

I've just registered to Oracle Cloud Free Tier.

After logging as ADMIN to SQL Developer Web, I've created a new user by executing the following statements:

CREATE USER MYUSERNEW IDENTIFIED BY "..............";grant create session to MYUSERNEW;grant connect to MYUSERNEW;

After giving logout, I've tried to connect as MYUSERNEW but I get:

An invalid user name or password was supplied.

Could it be that even if I've created a new user, oracle free platform allows to connect only by ADMIN?

Thanks!