Usually, when I have had issues with a short reed goose call locking up, it's for one of three reasons. (1) The reed tip needs to be able to drop into the tone channel .... even if it's just a little bit. If it can't .... you'll hear a "pfffftbbbdd" and the reed tip hits the tone board. (2) If the call isn't broken in, a pressure note (quick spit note, spit note, etc.) can cause the reed to lock up if you're pushing too much air through it, too hard. As the guts break in, this will stop. (3) The more common reason for the call locking up if you're not pushing too much air though the call is the reed tip touching the back of the tone channel. If you have the reed set very close to the end of the tone channel, with a minimum of clearance, the reed tip might be touching the back of the tone channel as it dips into it. Take your finger and slowly depress the tip of the reed into the tone channel. If it doesn't drop into the tone channel ........ there's your problem. If it drops into the tone channel, but you hear it rubbing, or clicking as it does .... there's your problem. You can either adjust the reed, or you can use a finger nail board to lightly sand away the portion of the reed which is touching. If you use a nail board, put something on top of the tone board so you don't scar the tone board in the process and sand away a little at a time where it's rubbing, trying the call in between.
I set my reeds very close to the end of tone channel, but still allow them to drop into the tone channel. I notice that with a new reed, the call will run clean and smooth .... but as the reed limbers up, it starts to slow down on note changes, requiring me to push more air into the call to run it. I normally just bend the reed tip up a bit. That provides enough clearance that the call runs smooth again.
I use a hemostat, bending the tip up about 45 degrees, then releasing it. You don't want a 45 degree bend in the reed tip, just bend it up that much and release. It will relax to about this point with use.
Reed is bent on the top side of the black line at the tip end of the reed.
Bent reed after it has relaxed with a little use.
Of course, the safe thing to do is to send the call back to the call maker to have him adjust it for you. You can tell him what your requirements are, and if he needs to make it run easier, he can shave the reed for you. Of course, since you didn't buy the call from him, he may charge you for his labor and certainly, you should send him money for return postage, in any case. When you get it back,use a Sharpie pen to mark the junction of the reed and wedge ... and if you have a dial caliper, you can measure the distance from the reed tip to the wedge and write that down for future reference, so you can get the call back to the same tuning point.