Skipping parts of the campaign by accident (POE2)

After the boss, when you speak with the NPC, my loot dropped and my inventory was full. So I thought I could just portal to town, but that resulted in me starting the reset for act1+, without me speaking to the npc. This is my first playthrough so I was very confused, I thought I had found a bug that resulted in my character going back to start.

I hope I didn't miss anything by not talking to the NPC at the end of the boss fight.

list of steps to replicate:
1. Don't finish the story by talking to NPC after final boss fight in ACT3.
2. Take portal to town, end up in BIC 400 version of town, take gateway.
3. Gateway triggers as if you took it from town after talking to NPC when you return to town.
4. You end up in ACT1+ with no interaction.


I was able to backtrack and talk to the NPC in town afterwards, but I guess it didn't matter as they don't give any rewards.