I also dump my ash when this happens, which is usually towards the end of a tall bowl.
It will go out, first I'll try lighting which either won't work or only produces enough ember for a few puffs before going back out. Then I move on to tamping which if it feels like it's already packed down and that doesn't change anything. I'll finally very carefully stir the top layer of ash making sure to feel where the "stiffer" tobacco that I want to keep is and work to not disturb that, and then dump it. That always gets it re-lit right away and then I can finish the smoke all the way down with little trouble.
I've never understood "the never dump ash" or "if you have to dump ash you've done something wrong" camp when smoking a cigarette or cigar it has the benefit of being open to the air, and the ash naturally falls off away from the ember. In a pipe, you don't have that open airflow around the sides or a nice open space for the ash to fall off into, so when the ash builds up it's got nowhere to go but on top of the ember, and get packed down as you tamp. It's always seemed logical to me that you would eventually need to dump that to get the airflow back, just like tapping your cigar to remove it.
Point is don't stress or feel like your "wrong" for doing this, do what works to get you a smoke you enjoy, and don't fret over any hard and fast "rules".