Downstream pipeline cannot be started

Child pipeline cannot be started

Describe your question in as much detail as possible:

I’m running a parent/child pipeline in a mono repo, for one child pipeline it runs fine, but for the other one i’m getting an error message on hover:
“downstream pipeline cannot be created”

I’ve simplified the the ci files to something very simple but no luck.

Gitlab self hosted version: 12.10.1 (e658772bd63)

Parent CI file

stages:
  - triggers

trigger_app:
  stage: triggers
  trigger:
    include: app/.gitlab-ci.yml
  rules:
    - changes:
      - app/*

Child CI file (app/gitlab-ci.yml)
stages:
- test

test:
  stage: test
  only:
    - pushes
  script:
    - echo "hello"

Ok worked out why: i removed the

only:
    - pushes

and it now works