subscription_callback never called

[JK-Pair]

Issue template

• Hardware description: ESP32-C6-WROOM-1
• Installation type: espidf, component - ESP-IDF 5.5v
• Version or commit hash: Humble

Steps to reproduce the issue

I have tested the publisher and subscriber from this repository and found that the subscription_callback is never called. On the other hand, the publisher works fine, even with a multithreaded subscriber.

Could anyone help point out any possible issues that might be causing this problem?

[Waelhechmi]

Hi @JK-Pair Make sure your subscriber is added to an executor and that the executor is regularly spun (e.g., rclc_executor_spin()), and check that the QoS of the publisher and subscriber match. Without the executor running or with incompatible QoS, the callback will not be called. and check number of subscriber on colcon.meta and idf.py clean and rebuild project for testing

you can add more information about error .