Dammit damnit damnit

For my online English literature class we had to do a bibliographical essay which was 40% of our grade. I turned it it, but due to issues with the software I was using the teacher told me to make revisions. I did so and I remember turning the revised version in on APril 28th. Today I was checking the online classroom and had an email from the teacher dated the 14th asking me for the revision as he needed to turn the grades in the following day(the 15th) I resent my revised version, but checked the submitted essay section and the essay had finally been graded at a 75% ARGGHHH!!