This document should be requested and dated close to your wedding date.
This document is the assurance that you are free from any canonical impediment for marriage.
a) These certificates must be obtained from the parish priest who baptized you, and must be dated within 3 months of your marriage.
b) If the date of your confirmation is not written in the parish you were baptized, you should ask for it from the parish in which you were confirmed.
c) Take these certificates to your current parish priest who should make the prenuptial inquiries and catechetical instruction.
Written permission must be obtained from your bishop
To have your marriage performed outside your parish and here in Santorini.
This is according to Canon 1115" of the Codex Juris Canonici. Please discuss with your pastor.