Finding And Listing Duplicates

I'm looking for some help in macro. I need to find duplicate from one column compared to another column then list them consecutively in another column. I have the rough macro working but need help making it more dynamic.

The user makes a selection of values in the first column manually. It then compares it to another column that I have to manually place the range numbers in the formula. I need the range to change in the formula each time a value is added to the compare to column. I tried with the letter z but the method error keeps coming up.

Also, the output column works but they don't list without having spaces between values.

I'm working at home & I don't have my notes and worksheets that I have at my work pc and my son asked me to do this for him this weekend.

Thank you, that works the way it should now. Is there any way the output column could list out in consecutive cells or does the formula cause the blanks to appear?

Thanks again. Had to leave for the weekend and just got back. This will make it work just the way my son described his need.