My window is falling down

Thanks for posting. It sounds like you need new window balances. Window balances are the spring mechanisms on either side of the sash that regulate its opening and closing. When the balances break, the window indeed cannot stay up. There are many different types of window balances. We'll need to see yours out of the window to get an idea of what replacements might work for you. Get started by reviewing everything to know about window balances here.