There's no such tab or link under online account where you can directly contact with IRCC, I just simply contacted them through webform (where we hv to select the right application, mention UCI number, application no, date of birth, email address and nationally etc, also under message box you need to write the message and it should not be more than 1500 character's) I also sent email to Abu Dhabi embassy on this address:please share the complete information that how you did this,
after refusal- which link or tab you clicked on CIC web?
on which email your contracted them?
ABDBIIMMIGRATION@international.gc.ca
But I didn't receive any reply for my email but I got email from this address that they are going to send my case to migration officer and below the email message i found all my content which i wrote in webform. (why I said I didnt received any reply from above email coz I remember I wrote in more details about my refusal since there wasn't any restrictions for words counts)