Basic Error Adding Field Augmentor

Same thing did happen to me:

Error message
There was a problem creating field augmented field: The "field_token_value_text" plugin does not exist.

1. Bare integration to CKEditor 4

the DISPARATE result - an empty set of augmentors.
After enabling an additional module Demo Augmentor and creating a key with: {key type - authentication, key provider - configuration, key value - anything},
upon highlighting of a fragment of a text it just duplicates an original one to the string below

Beforehand an augmentor type must be added: /admin/config/augmentors

2. Add a new Augmentor field

(/admin/structure/types/manage/.../fields/add-field) in this case, only an error emerges.
Neither a tab nor something else is visible in the node create template.

3. with OpenAI GPT3 Augmentor enabled:

• when trying to edit newly created OpenAI GPT3 Completion

Error: Class "Orhanerday\OpenAi\OpenAi" not found in Drupal\augmentor_openai_gpt3\OpenAiGPT3Base->getClient() (line 36 of modules/contrib/augmentor_openai_gpt3/src/OpenAiGPT3Base.php).

Drupal\augmentor_openai_gpt3\OpenAiGPT3Base->getClient() (Line: 285)
Drupal\augmentor_openai_gpt3\Plugin\Augmentor\OpenAiGPT3Completions->engines() (Line: 61)
Drupal\augmentor_openai_gpt3\Plugin\Augmentor\OpenAiGPT3Completions->buildConfigurationForm() (Line: 112)
Drupal\augmentor\Form\AugmentorFormBase->buildForm() (Line: 18)
Drupal\augmentor\Form\AugmentorEditForm->buildForm()
call_user_func_array() (Line: 534)