At which block is your wallet stuck right now?
First of all make sure you are using the latest version of the Lines wallet (I mean lines-gui-win64.0.3.2). Then try to delete your Lines folder in C:\Users\username\AppData\Roaming (make sure you have made a backup of your wallet! We won't be able to rescue your coins if they are lost) and relaunch your wallet to resync it once again.
That should do. I've just made a test, my wallet was synced 31 days ago and everything went fine.