In case you're eligible to e-file your Federal tax return you would need to have MFA enabled in your Sprintax account.
You can enable MFA through a passkey, SMS or an authenticator app.
Please visit the following articles for each MFA method available:
How to Enable an Authenticator App for MFA?
How to Enable a Passkey for MFA?
After you have successfully authenticated yourself, Sprintax will confirm that you have e-filed your Federal tax return and this text will pop up:
For more information on e-filing, you can visit this link.