P0442, Help, fix for emmmision. on 1996 Pontiac Sunfire

Change gas tank and erase OBDll, check gas filter and tank for leakers and found nothing, however, it come back

2 answers
Most likely causes are: fuel filler cap is loose and need a new one due to gasket wear, fuel filler neck has rusted and there is a hole breaking the vacuum or an evap system hose is leaking. Best way to find the leak is with a "smoke test" at a shop.
. . vm.