Did the problem with the Drag start after you serviced the reel, or did it just start up out of the blue?
If suddenly, then it could be that the top drive shaft Bearing is seized;
If it's after you opened it up, then it could be many things.
1. Look at the 2 drag spring washers, they should be aligned () not ((
2. Make sure you have all the parts installed according to the schematic drawing