Elements are lost in linked lists

This should be an easy one, but I can't spot the mistake and I am going nuts. I have the following structs:

struct bucket {
        o_list::Node* pointers;
        unsigned int size;
        unsigned int length;
};

struct Node {

        short data[N];
        long norm;
        Node *next;
        Node *next_in_bucket;
        char lock;

};

and the following functions:

void bucket_add(bucket* b, o_list::Node* v){

    v->next_in_bucket = b->pointers;
    b->pointers = v;
    b->length++;

}

void bucket_remove(bucket* b, o_list::Node* v){

    o_list::Node *sentinel = b->pointers, *prev;

    if(b->pointers==v){
            b->pointers = b->pointers->next_in_bucket;
            b->length--;
            return;
    }
    else{

            prev = sentinel;
            sentinel = sentinel->next_in_bucket;

            while(sentinel){
                    if(sentinel == v){
                            prev->next_in_bucket = sentinel->next_in_bucket;
                            b->length--;
                            return;
                    }
                    else{
                            prev = sentinel;
                            sentinel = sentinel->next_in_bucket;
                    }
            }
    }
}

At some point I have bigger "sizes" than elements in the lists. I do not free the elements on purpose! Is there any error here?