do you click the "broadcast" button at the bottom of the window that appears after you sweep your private key? the same window that shows you the transaction ID.
this window is like a "Preview" if your transaction information and based on your wallet settings you may need to manually click the broadcast button to send it out to the network.
as you can see this is a test transaction i just created, signed but never broadcast so it is not out there although i have a transaction ID.
https://i.imgur.com/blCjKw1.jpg
in case this is no your issue, then it is because there is something wrong with your transaction (for example double spend or 0 fee) which causes the Litecoin Network to reject your transaction.
I'm actually retarded and no I didn't click that. I had no idea what the broadcast button actually did. Thank you so much I will try now and get back to you. As you can see I'm still a crypto newbie..
Yes so I clicked broadcast and it worked... and to think my private key was exposed for so long since I entered it like 3 times... Learned a valuable lesson today.