I have codes that say evap emissions system incorrect purge flow what can I do

P0441-EVAP PURGE FLOW MONITOR When Monitored: With engine temperature greater than 170° F, fuel control in closed loop, engine idling for 2 minutes, no low fuel, MAP less than 15.7 inches mercury and barometric altitude less than 8,000 feet. Set Condition: After having passed the Leak Detection Pump (LDP) test, no air flow through the evaporative system is detected by the EVAP monitor. Possible causes are; EVAP CANISTER WIRING HARNESS INTERMITTENT EVAP PURGE HOSE (CANISTER TO FUEL TANK) EVAP PURGE HOSE (SOLENOID TO CANISTER) EVAP PURGE SOLENOID VACUUM SUPPLY EVAP PURGE SOLENOID (LEAKY/STUCK OPEN) EVAP PURGE SOLENOID (STUCK CLOSED)