Used my Mastercard Black to upgrade do Sixt Cards Platinum. Sent an e-mail to firstname.lastname@example.org
with de text:
I would like to request my upgrade to the SIXT PLATINUM level, through the currently valid partnership between SIXT and MASTERCARD BLACK.
Please find below the information needed to process my upgrade:
ID from my country (your country here):
Sixt Card Number: (photo)
MasterCard Black: (photo)
The match happened in 2 days.