How to Revive NPC and Reset Aggro Merchants - Elden Ring
First, you have to attack (but don't kill) the merchants.
And verify he is still hostile after fast traveling.
After that, go to an important NPC location.
Use Furlcalling finger remedy.
And find a golden summon sign.
You will need to summon a Cooperator.
Go into a mist with a cooperator.
And beat the mad pumpkin head.
You have to activate grace to travel back here later.
Open the door to meet an important character.
And talk to Sellen ( an important NPC).
You need to attack Sellen until she disappears.
Then fast travel back to verify she is gone.
Fast travel to the main academy gate.
After that, move down the left side to the gate.
And grab a celestial dew.
Now you have to fast travel to the Church of Vows.
Enter church of vows.
And show Miriel the celestial dew.
Next, you have to go to the statue to use celestial dew.
Sins absolved, go back to merchant.
You need to verify merchants are no longer aggressive.
Fast travel to important NPC locations.
Verify important NPC is revived.