You would do good to consult the documentation instead of waiting for someone to fix your script, which won’t happen unless it’s a fantastic learning opportunity for both parties. It’s just quicker!
Plus, you don’t need to read the ~3000 pages of the manual. Just head to the delete_atoms command, it’s all written there.
Also, please read the forum guidelines before posting, you will spare us the misery of reading badly formatted code.
Regarding your script, you defined a region Traget and referred to it as target in the following command. It’s pretty easy to make typos, but you could at least proofread your code before jumping to the forum. It’s degrading to ask other people to do it for you.