Error when wanting to install the Point of Sale module

Odoo 12

​Error:

Odoo Server Error



Traceback (most recent call last):

  File "/opt/odoo/odoo/odoo/tools/cache.py", line 88, in lookup

    r = d[key]

  File "/opt/odoo/odoo/odoo/tools/func.py", line 69, in wrapper

    return func(self, *args, **kwargs)

  File "/opt/odoo/odoo/odoo/tools/lru.py", line 44, in __getitem__

    a = self.d[obj].me

KeyError: ('ir.model.data', <function IrModelData.xmlid_lookup at 0x7f7f25a93d90>, 'product.product_category_1')



During handling of the above exception, another exception occurred: