got reply from IRCC CSE/Web form...
Thank you for contacting Immigration, Refugees and Citizenship Canada (IRCC).
There could be a few reasons why you were unable to link your application:
1. You entered information that is different from what you submitted on your application
The information you enter to link your application must match what you had on your application when you submitted it. If you updated information after you submitted your application, enter the most recent information we would have on file.
You can try to link an application five times. If you are unsuccessful after five attempts, you will be locked out for 24 hours.
2. An immigration representative is handling your file
If you have hired a representative, only that representative can access the application status through the Authorized Paid Representatives Portal. You must remove the representative from your file to link your application.
If you chose to do so, upload the Use of a Representative (IMM 5476) form to your account, with cancelling the appointment of a representative selected on the form. Once that information is processed, you will be able to access information about your application.
If you need to update your representative information, please visit our website.
3. Our system could be down
Please visit our website.
After attempting to link your account, if you receive the response there are no matches, it could be for two reasons:
1. You entered the information incorrectly
The system will only link your application if the information you enter matches what you had on your application exactly. If you contacted us after you applied and updated any information, provide the most recent information.
2. Your application hasn’t been entered into our system yet
If you applied by mail or in person, it may take some time for it to be entered into the system. Once we have it entered, you will be able to link your application.
If you are still experiencing difficulties, please fill out the IRCC Web form available on our website and choose Technical difficulties located in the drop down menu under the heading Enquiry. Also add the following information:
Any error messages you received. To do this:
provide us with screen shots of:
the full browser window,
the page you are trying to access, and
the error message.
All the answers provided while trying to link your application. To do this:
once on that page, provide us with screen shots.
Sincerely,
Immigration, Refugees and Citizenship Canada