Wont Open!!

My wedding is in 5 MONTHS!! Ive been so busy (since I just got engaged literally a week 1/2 ago) & have been using this app to save information & havent yet gotten the chance to write everybodys addresses down on paper!!
Everything was going fine until I tried to open it today to save a new address, & it wont even open! I dont want to delete for hope that my addresses will be saved!
PLEASE HELP.

Rlorraine14 about Wedding Guestbook by The Knot