code: protected function fillSoftDelete(Model $record, $field, $value)
      {
          $value = $this->deserializeSoftDelete(
              $value,
              $field,
              $record
          );
  
          $record->forceFill([
              $this->getSoftDeleteKey($record) => $value,
          ]);
      }
docs: Fill the soft delete value if it has been provided.
  
  @param Model $record
  @param string $field
  @param mixed $value