It takes about 3 weeks for both "Fingerprints received" and if applicable, "Background completed" status to update after the fingerprints have been sent to IRCC.
You can do two things if it is taking a while:
1. Contact RCMP: You will need the DCN number you may have got from the fingerprinting agency. Note: The response takes a while. In my case I received an RCMP reply after my status had been updated in tracker. There is also a phone number for CCRTIS but I never managed to reach them over phone.
2. Reply back to the email that sent you a fingerprinting request. You will get an auto-reply saying that we don't respond to status requests. But in many cases mentioned on the forum, the status updated in tracker soon after. I think this is probably not making a difference and IRCC was going to update it any way soon.
3. Order GCMS notes: Your fingerprints may have been received and you may have passed criminality check. But there may be other checks in progress that are preventing background being completed. You may be able to find out if this is so from GCMS notes. The notes are unlikely to provide you with any useful info to speed up your application.
Hope this helps. Nothing is legal advice in the above. Just trying to help.