Issues with moving map in curses in c

Question

I am working on 2d terminal game like space invaders but with moving map. I have a issue where the map moves to the top and after reaching the top edge it changes characters of another wall coming towards the player any tips?

void moving_map(){
    initscr();
    int i = 0;
    char map1[50][150];
    char map2[50][150];
    char zone[50][150];

    //prva mapa inicializacia pre prvych 50 riadkov
    entities(zone);
    generator(map1,zone);
    for(int k = 0; k < 50;k++){
        for(int j = 0; j < 150;j++){
            mvprintw(k,j,".");
            map2[k][j] = map1[k][j];
        }
    }
    ship();
    refresh();
    delay(2000);
    int test = 0;
    int x = 0;
    while(true){
        if(i == 49){
            //nasledna inicializacia pre dalsich 50x riadkov
            srand(time(NULL));
            entities(zone);
            generator(map1,zone);
            i = 0;
            for(int q = 0;q<50;q++){
                for(int j = 0;j<150;j++){
                   map2[q][j] = map1[q][j]; 
                }
            }
        }
        for(int q = 0; q <= i;q++){
            for(int j = 0; j < 150;j++){
                mvprintw(49-q,j,"%c",map1[i-q][j]);
                if(q == 48){
                    test = 1;
                }
                if(test == 1){
                    x = 0;
                    for(int p = 48-q; p > 0; p--){
                        mvprintw(p,j,"%c",map2[x][j]);
                        x++;
                    }
                }
            }
        }

        ship();
        delay(100);
        refresh();
        i++;
    }
    getch();
    refresh();
    endwin();
}

triple wall segment After the triple wall segment reach the edge it its changing another wall segment coming after it.

Thanks for help.