The touch functionality is controlled by the Digitizer cable which stems off of the top of the screen assembly you purchased from iCracked. If this cable gets damaged at all when performing the installation, it will cause that portion of the repair not to work. When we say damaged, we mean any bends, creases, kinks or tears in the cables themselves. These are "flex" cables and are meant to do so, but a serious score, such as one you would make when folding a paper airplane will effectively cause that portion of the assembly to not work. The same thing could happen to the LCD cable.
If you have done the repair and are experience no touch functionality, please re-open the device and inspect the cables for the damage we have described. If you have damaged it, please reach out to iCracked support as we provide a 25% off coupon code for these situations. If you do not see the damage that we have described, please photograph the cables and send them to firstname.lastname@example.org. When you send those photos, please also include your name, order number and a brief description of the situation. Once we get it here, we will run it through our warranties team and get back to you immediately.