Extruder clicking noise, extruder won't load filament

Last time I printed a project it ran out of filament during the run, but I didn't realize that it had stopped for that reason (as it was 90% done and looked finished). It was only after I turned off the machine and removed the print that I realized it had run out of filament prior to finishing.When I went back to load new filament today, the extruder was making a clicking sound and wouldn't load the filament. I thought it might be an issue with the tension on the screw, so I adjusted that. Now it doesn't make the clicking sound anymore, but it still isn't feeding the filament through the extruder.What is the issue? How do I fix this?