Man pages matching name vm::ec2::instance::state::reason in section 3pm:

VM::EC2::Instance::State::Reason.3pm.en	debian 10 / libvm-ec2-perl
VM::EC2::Instance::State::Reason.3pm.en	debian 11 / libvm-ec2-perl
VM::EC2::Instance::State::Reason.3pm.en	debian 12 / libvm-ec2-perl