Brisket is a tough cut sometimes.

Each one is different from the next.

A few things that might help if you haven’t tried them yet :

If you’re doing a full packet brisket separate the point from the flat. They both cook at different speeds so if you’re having trouble you can pull one off when it’s done and let it rest while the other finishes.

Texas crutch by wrapping in butcher paper or aluminum foil when it gets to the “stall” stage or whenever you think it’s got enough smoke 6-8 hours in.

Try and go by feel next time you toss one on. Get a meat thermometer if you don’t have one and when it starts getting up around 190° own it with the thermometer. When the thermometer slides in t like it’s going into jelly your brisket (or pork shoulder) is done. It may be done at 190 or 200 or 205 each one is different.

Lastly DO NOT cut it immediately but wrap it in a few layers of foil, then a couple towels and stick it in a cooler for an hour up to 8 hours. Let it rest and “reabsorb” some juices.