If you got your NETFILE confirmation number, then you return was successfully sent.
If you are having problems registering for MyAccount, you will need to contact the CRA for assistance.
If you are in Canada or the United States, you can call the CRA at 1-800-959-8281. If you are elsewhere, you can call 613-940-8495. This page has more ways to contact the CRA: Contact the Canada Revenue Agency.