Sounds like you are deploying the dive brakes? Are you sure you deploy the gear with "G" and not with "B"?
Did you break the tailwheel by any chance? Like slamming the tail onto the ground, for example when braking?
And the hook will only come down if the tail wheel is down. If the tail wheel isn't deploying, you won't get a hook either.
Also, feel free to attach a short track so we can see more details.