You need to increase the amount of available storage on your phone to install Lollipop. I made enough room for 3GB of available space. I did have about 1GB. You need to remove apps or move them to the SD Card. To see how much you have:
Go into Settings.
Select More
Select Storage
To remove or move Apps:
Go back out to the More menu again
Select Application Manager
Select an App
If you have an SD Card and the Move to SD Card is not grayed out, you can move it to the SD Card. Otherwise, you can Uninstall it.
Do this for all the Apps you have to make more room.
Go back to the Storage Menu
Clear your Cached Data
Try to reinstall Lollipop again. If you are getting the,"You must wait XX hours and XX minutes, go to Data and Time, Turn off update automatically and advance the date by at least 1 day and go back and reinstall Lollipop.