Recently, a change was made to the way reports are submitted. You still enter the details, choose the replay and so on but you cannot submit the report from in-game. You must now visit MyCTRA to submit the report.

If you do not go into MyCTRA to submit your report then it cannot be processed. There are a lot of stored, but unsubmitted reports. If you have recently made a report then please make sure you submit it, or delete it if you're no longer sure.

There is a guide to explain how to make a good report here.