You pruned model is in a pruned reparametrization state, where pruned weights have been replaced as such: weight --> weight_orig, weight_mask.
Now, if you try to load those into an unpruned model via a state_dict, it will of course fail, because that reparametrization doesn’t exist in your unpruned model, and the keys in the state_dicts don’t match.
Instructions on how to solve this are provided in these answers: Proper way to load a pruned network 14
Let me know if you have any further questions.