Can't cast guild.getMembers() to arraylist

[Slaymish]

Current line:
ArrayList<Member> scrimMems = (ArrayList<Member>) scrimOrg.getMembers();

Error:
Exception in thread "Timer-0" java.lang.ClassCastException: class java.util.Collections$UnmodifiableRandomAccessList cannot be cast to class java.util.ArrayList (java.util.Collections$UnmodifiableRandomAccessList and java.util.ArrayList are in module java.base of loader 'bootstrap')