php - How to fix 'Not acceptable format: json' message

one text

I have created a new entity panel_caption_label in my project drupal and activated API route for GET this entity.

My rest.resource.entity.panel_caption_label.yml config file ?��???

uuid: da80fe4a-c7ec-49b2-94eb-9afaa69fe399
langcode: fr
status: true
dependencies:
  module:
    - atlantic
    - serialization
    - user
id: entity.panel_caption_label
plugin_id: 'entity:panel_caption_label'
granularity: resource
configuration:
  methods:
    - GET
    - POST
    - DELETE
    - PATCH
  formats:
    - json
  authentication:
    - cookie

But when I try to do a GET http://localhost:950/api/panel-caption-label/panel_caption_label?_format=json

I get this message ?��???

{
    "message": "Not acceptable format: json"
}

I have tried to export config and import manually, but nothing work...

How to fix it ?

Thank a lot !

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