i see this error when i want to validate product that receive 

what is this error?how can fix this?

Error:

Odoo Server Error

Traceback (most recent call last):

  File "C:\Program Files (x86)\Odoo 13.0\server\odoo\http.py", line 619, in _handle_exception

    return super(JsonRequest, self)._handle_exception(exception)

  File "C:\Program Files (x86)\Odoo 13.0\server\odoo\http.py", line 309, in _handle_exception

    raise pycompat.reraise(type(exception), exception, sys.exc_info()[2])

  File "C:\Program Files (x86)\Odoo 13.0\server\odoo\tools\pycompat.py", line 14, in reraise

    raise value

  File "C:\Program Files (x86)\Odoo 13.0\server\odoo\http.py", line 664, in dispatch

    result = self._call_function(**self.params)

  File "C:\Program Files (x86)\Odoo 13.0\server\odoo\http.py", line 345, in _call_function

    return checked_call(self.db, *args, **kwargs)

  File "C:\Program Files (x86)\Odoo 13.0\server\odoo\service\model.py", line 93, in wrapper

    return f(dbname, *args, **kwargs)

  File "C:\Program Files (x86)\Odoo 13.0\server\odoo\http.py", line 338, in checked_call

    result = self.endpoint(*a, **kw)

  File "C:\Program Files (x86)\Odoo 13.0\server\odoo\http.py", line 909, in __call__

    return self.method(*args, **kw)

  File "C:\Program Files (x86)\Odoo 13.0\server\odoo\http.py", line 510, in response_wrap

    response = f(*args, **kw)

  File "C:\Program Files (x86)\Odoo 13.0\server\odoo\addons\web\controllers\main.py", line 1323, in call_button

    action = self._call_kw(model, method, args, kwargs)

  File "C:\Program Files (x86)\Odoo 13.0\server\odoo\addons\web\controllers\main.py", line 1311, in _call_kw

    return call_kw(request.env[model], method, args, kwargs)

  File "C:\Program Files (x86)\Odoo 13.0\server\odoo\api.py", line 395, in call_kw

    result = _call_kw_multi(method, model, args, kwargs)

  File "C:\Program Files (x86)\Odoo 13.0\server\odoo\api.py", line 382, in _call_kw_multi

    result = method(recs, *args, **kwargs)

  File "C:\Program Files (x86)\Odoo 13.0\server\odoo\addons\stock\wizard\stock_immediate_transfer.py", line 34, in process

    pick_to_do.action_done()

  File "C:\Program Files (x86)\Odoo 13.0\server\odoo\addons\stock\models\stock_picking.py", line 705, in action_done

    todo_moves._action_done(cancel_backorder=self.env.context.get('cancel_backorder'))

  File "C:\Program Files (x86)\Odoo 13.0\server\odoo\addons\stock_account\models\stock_move.py", line 246, in _action_done

    valued_moves['in'].product_price_update_before_done()

  File "C:\Program Files (x86)\Odoo 13.0\server\odoo\addons\stock_last_purchase_price\models\stock.py", line 40, in product_price_update_before_done

    raise UserError(_('Configuration error. Please configure the price difference account on the product or its category to process this operation.'))

NameError: name '_' is not defined