complete file, rec'd confirmation then message rejected. Acct is now locked.

[lar]

completed online file, rec'd confirmation then clicked send and message rec'd rejected.  Acct now locked

[Geo123]

Hello lar,

RE : Error 15
The CRA has locked your account due to too many failed attempts to NetFile (5xTimes maximum). You should contact the CRA to **unlock the account ie specifically the transmission to Netfile ** and then wait at least 12 hours to NetFile.  
Please note there is a difference between CRA myaccount and the CRA Netfiling account and not all CRA agents are aware of this.  
Unfortunately there is nothing that we can do.
Of note, you can also print and mail the tax return.
CRA Tel. : 1-800-267-6999