vs-code editor for yaml says expecting a map but found a sequence

i'm editing a main.yml in an ansible role's tasks folder.

i'm using the YAML vscode extension by Red Hat.

Here's the first part of the file...

# Install Packages
- name: Install the Kafka Broker Packages
  yum:
    name: "{{item}}-{{confluent.package_version}}"
    state: latest
  loop: "{{kafka_broker_packages}}"
  when: ansible_os_family == "RedHat"

- name: Install the Kafka Broker Packages
  apt:
    name: "{{item}}={{confluent.package_version}}"
    update_cache: yes
  loop: "{{kafka_broker_packages}}"
  when: ansible_os_family == "Debian"

the entire file has the red squiggly underline saying:

Expecting a 'map', but found a 'sequence'

i'm sure i'm doing something silly - any help is greatly appreciated