In accordance with Article 14(1) of the Commission Delegated Regulation (EU) 2018/389, Platform.sh has implemented strong customer authentication (SCA) for customers using payment methods from the EU.
The article states:
SCA is part of the Revised Payment Services Directive, acting as a regulatory requirement to reduce fraud and to make online transactions more secure.
The law went into effect September 14, 2019, and European card holders have been required since October 1, 2019 to authenticate recurring payments with their payment institutions.