Cant download the update..?

Ive a 16gb iPhone and I usually delete my previous tomtom app to update whenever theres an update (due to an insufficient available space). This time Ive deleted the existing one and couldnt get the new one to download ?? Anyone is having a same issue.. Pls fix ASAP! Thx

Shane101d about TomTom U.S. & Canada, v1.21.2