Stupid question but i have to ask...
Did you replace the correct flasher?
This will have separate flashers for the signals and the 4 ways....
Front seating area, driver side, under dash, driver side of steering column, mounted on support bracket
Turn signal flasher Location
Front seating area, driver side, under dash, above kick panel, mounted in top of convenience panel
Hazard flasher location....
If you did,then it sounds like the turn signal switch (Multifunction Switch) itself is faulty..