My hair will not curl?

I have naturally straight hair (not SUPER straight, but pretty close) and it's very silky and soft. I can scrunch it effectively, but when I try to use a curling iron or curl with a straightner, it won't curl in some places! It curls in some places, but in the back, no matter how long I hold it or what method I use, it is still straight. :/ ugh.





Could this be because I have silky thin hair or something, I heard this could be a reason? What products/methods can I use to fix this?My hair will not curl?
i have really straight and silky hair too and i would use volume conditioner im a teen so lol i would know and make sure you hair isnt greasy make sure you wash it every night and use hair spray after curlingMy hair will not curl?
you can get a perm or you can use hair spray and a vigo perhaps.