Q: Trouble syncing the music from my pc laptop to my iphone

When i try to sync the music from my laptop, a message pops up and tells me: "The iphone cannot be synced because there is not enough free space to hold all the items in the itunes library(additional 3.02 GB required)". I have checked my laptop's free space and there is 633 GB of space on it's hard drive. i don't understand why it won't let me sync my music onto my iphone. Also literally right before that, i deleted over 200 songs off of my itunes and now i only have 787 songs. My iphone still holds 839 songs which is over 100 songs that i would like removed. I didn't want to add songs only remove them so even if it's a space issue on my iphone it doesnt make sense because i'd be creating space not taking away and plus i still have 1.17 GB space on it. Can somebody please explain why i cant do this it's really bothering me because if i cant even remove songs from my iphone, that means i cant add them!!