My Rocoh FT 4220 leaves a blank strip across every

Clean the optical section(glass,mirrors,lems)Verify the paper dust on the edge of the cleaning blade,if the OPC drun scratched or the fusing hot roller scratched.Press the cleaning blade release lever down several times.Make a copy and stop the machine when the paper reaches the transport section.If the lines appear replace the OPC drum.After replacing the drum perform the Drun initial setting,Light Intensuty Adjusment,ADS voltage adjustment,Vsg adjustment.