If you are talking about Less/Alfajer that's because they were grandfathered in.
Vct Roster Construction rule book 2023 (section 2.12):
Grandfathering. As an exception to the Minimum Age Requirement in Section 2.1.1. above, an individual that competed in a Challengers main event in any VCT League in 2022 and was born between March 26, 2005 and March 26, 2006, is eligible to participate if a parent or legal guardian accepts all of the rules and policies of the League on behalf of the individual, and consents to the individual participation using a parental consent form provided by the League Entity.