How to completly remove a field?

I have removed a field from a bundle (it is not used somewhere else) by using the graphical UI.

But it is still listed when I run the following command (after cache clear)

$this->entityFieldManager->getFieldDefinitions('node', $bundle); 

What should I do to completely remove it (as I use the previous command to display some list)

edit to add:

Following the proposal of Clive, I ran the field_cron() without success. Looking at the code of this function, I tried the following code to have more information:

$deleted_fields_repository = \Drupal::service('entity_field.deleted_fields_repository');
$fields = $deleted_fields_repository->getFieldDefinitions(NULL);

As you can imagine, $fields is empty. Maybe some kind of corruption?

edit to add 2

Following the proposal of 4k4 I ran this code:

$field_storage = \Drupal\field\Entity\FieldStorageConfig::loadByName('node', 'the_field_that_must_be_deleted');
dpm($field_storage->get('persist_with_no_fields'));

And the result is FALSE

Thus the question is: how to manually remove a field?

Usually you would just run cron for this, because field_cron() clears the deleted data.

If you need to do it manually for whatever reason, you can call field_purge_batch() manually.