Return the part and get a new one, as long as it was unplugged and not just turned off.
The reset is initiated by power on after being unplugged. Did you happen to replace it when it was turned off but still plugged in?
If so, shut down, unplug, wait a few minutes and plug it in and turn it on.
I recently replaced a fuser from Xerox Phaser 4600. The LCD screen keep showing "Replace Fuser" error. I tried to look for the options to reset the fuser counter but cannot find it.
Any suggestion on how to reset the fuser?