Hello and thanks for your question. I look forward to assisting you today with the best answer possible.Are you trying to reseat all the ink tanks or any particular one?
Is it the operational cover which you're not able to close?
After reseating all the ink tanks, did the lights glow red on all of them
Is your printer not ON?
I'll give you a manual on how to replace the ink tanks on your printer. Please remove the inktanks from your printer and then follow each and every instruction in the manual to reseat it again.
Please don't skip any instruction in the manual.
Please click here to access the manual: https://support.usa.canon.com/kb/index?page=content&id=ART142961&actp=search&viewlocale=en_US&searchid=1466219171629
Tell me if it makes any difference.