I was called to defend Nordhaven Beach and successfully defended it from a Synth attack.

But despite one of the NPCs acknowledging the attack is over, the mission does not complete!

I can't leave the area because the mission will fail.

I have searched the area throughly and cannot find an enemy to attack or a npc to talk to about it.

I couldn't even find the mission id to forcecomplete it with console commands.

What course of action should I take?

Just walk away and let them mission fail?

And what are the consequences for the Minutemen if I do this?