If you used Online TurboTax for your 2018 return, here's how to recover account access, reset password, etc. You may have more than one account. Many people end up with multiple accounts without realizing it.
To get a list of your User IDs and recover account access, reset password, etc., you can use the tool at the link below. Try using your phone number in the tool first. After that, if necessary, then run the tool on your email address(es) you can access.
NOTE: Before running the account recovery tool below, log out of all Intuit accounts including this user forum, or you might end up in a loop. Then clear your browser Internet cache, close your browser, then reopen it, and go to the link below. You may wish to copy this link so you can paste it into the new browser session.
https://myturbotax.intuit.com/account-recovery
If still no luck after running that on your phone number and email address(es) that you can access, here's another method:
Go back to the tool again, but this time leave the data field blank, and choose the small blue link that says "Try something else", and it will look you up by SSN and other parameters.