Corrupted data. clear the all the jobs from the que. restart the machine and this will fix. if not means bad hard drive. I’m happy to help further over the phone at https://www.6ya.com/expert/mustafa_06f84c65ab5cc745
Heat code. You will need to reset in service mode.1087 1087 function find reset fixing assembly and activate. If it comes back you have a bad bulb or a bad thermistor. Could be a thermal switch . It's the fuser assembly.
First you have to find out where the paper jam occurs. Check the Rollers and the clutches, then the sensor for the registration and finally the exit sensor. Clean or replace any defective part.