PoE 2 - Softlocked in "The Trail of Corruption" quest bug

Hello,

My character was sounding the horn in the caravan as part of the task "Use the Horn of the Vastiri to clear the sandstorm" in "The Trail of Corruption" quest in Act 2. I had just clicked the in-game prompt to do this, but suddenly the servers crashed and I got disconnected. This was a few minutes ago.

Now the game still requires me to do this, but the action prompt at the front of the caravan doesn't appear anymore, which makes progress impossible.

I've tried dropping the Horn and getting it from Zarka again, but it didn't work. I tried clearing the "Halani Gates" area again to reach the sandstorm area, but it simply repeats a previous part of the questline and doesn't change anything.

I've invested quite a few hours in this character at this point, and I wouldn't want to lose it. Would it be possible to fix this? Thanks in advance.