Where do I report bugs with the STACK app/card? Mike June 09, 2020 19:00 Updated Follow We are always looking to fix any bugs we encounter with the STACK app & card. If you encounter a bug, please report it here! Related articles Who can apply for STACK? What is your partnership with Mastercard? FAQ Français What is STACK? How do I get my card PIN? + Change my card PIN? Comments 0 comments Article is closed for comments.