Repair: implicit sampling_size for statistics entity

Hi,
I’m getting a warning in my repairs section about some statistics entities. It links to this PR: https://github.com/home-assistant/core/pull/69700

In the warning and in the documentation for the statistics integration it states that sampling_size OR max_age must be specified.

I have specified max_age but still get the warning? What am I doing wrong?

platform: statistics
entity_id: sensor.processor_use
name: CPU Usage Statistics
state_characteristic: mean
max_age:
  hours: 12