So, I was sweeping private keys into Electrum and on the first one I swept, I got the successful transaction pop up, but I didn't click "Broadcast" as needed to add them to my wallet, I just clicked the close up button, because I thought I already had them in the wallet and broadcast was used to send them to another wallet/exchange. When I closed the window and realised I didn't have them there, I tried doing the same again, but I never got the Sweep button as a viable option, it was just grey and I couldn't click it. So, I tried sweeping it in WIF through Coinomi. But this didn't work either, because when I went to liteaddress.org and clicked on wallet details in order to get my private key in WIF, the key was never shown. I just got an empty form and where my keys in different formats had to be, there was just empty white space.
Could anybody please help me find a solution to my problem, because for the past 2 days I have been trying to sweep them with no success. Thank you a lot and have a great day!