When I tried to change the old template header by the new one, it happend. What should I do now. Please help me, I am building a website for my class term. 

Error while render the template
ValueError: Không thể định vị phần tử '' trong chế độ xem mẹ
Template: website.layout
Path: /t/html/body/div[2]/header/t/t[1]/div/div[2]/t
Node: 

The error occurred while rendering the template website.layout và đánh giá biểu thức sau: 

Traceback (most recent call last):
  File "/home/odoo/src/odoo/17.0/odoo/tools/cache.py", line 99, in lookup
    r = d[key]
  File "", line 2, in __getitem__
  File "/home/odoo/src/odoo/17.0/odoo/tools/func.py", line 87, in locked
    return func(inst, *args, **kwargs)
  File "/home/odoo/src/odoo/17.0/odoo/tools/lru.py", line 34, in __getitem__
    a = self.d[obj]
KeyError: ('ir.qweb', , ('(\'842\', "\'vi_VN\'", \'True\', \'False\', \'None\', \'None\', \'None\', \'1\')', 'template_842_t_cache_22_cache', ("'website.homepage'", 'website', (1,), 1700905305.935478, 'False')))

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "", line 1710, in template_842
  File "", line 1470, in template_842_content
  File "/home/odoo/src/odoo/17.0/odoo/addons/base/models/ir_qweb.py", line 2507, in _load_values
    value = self._get_cached_values(cache_key, get_value)
  File "", line 2, in _get_cached_values
  File "/home/odoo/src/odoo/17.0/odoo/tools/cache.py", line 104, in lookup
    value = d[key] = self.method(*args, **kwargs)
  File "/home/odoo/src/odoo/17.0/odoo/addons/base/models/ir_qweb.py", line 2520, in _get_cached_values
    return get_value()
  File "", line 1460, in template_842_t_cache_22_cache
  File "", line 1071, in template_842_t_cache_22
  File "", line 973, in template_842_t_call_23
  File "", line 5, in not_found_template
ValueError: Không thể định vị phần tử '' trong chế độ xem mẹ

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/home/odoo/src/odoo/17.0/odoo/http.py", line 1732, in _serve_db
    return service_model.retrying(self._serve_ir_http, self.env)
  File "/home/odoo/src/odoo/17.0/odoo/service/model.py", line 133, in retrying
    result = func()
  File "/home/odoo/src/odoo/17.0/odoo/http.py", line 1759, in _serve_ir_http
    response = self.dispatcher.dispatch(rule.endpoint, args)
  File "/home/odoo/src/odoo/17.0/odoo/http.py", line 1873, in dispatch
    return self.request.registry['ir.http']._dispatch(endpoint)
  File "/home/odoo/src/odoo/17.0/addons/website/models/ir_http.py", line 235, in _dispatch
    response = super()._dispatch(endpoint)
  File "/home/odoo/src/odoo/17.0/odoo/addons/base/models/ir_http.py", line 209, in _dispatch
    result.flatten()
  File "/home/odoo/src/odoo/17.0/odoo/http.py", line 1248, in flatten
    self.response.append(self.render())
  File "/home/odoo/src/odoo/17.0/odoo/http.py", line 1240, in render
    return request.env["ir.ui.view"]._render_template(self.template, self.qcontext)
  File "/home/odoo/src/odoo/17.0/addons/website/models/ir_ui_view.py", line 443, in _render_template
    return super()._render_template(template, values=values)
  File "/home/odoo/src/odoo/17.0/odoo/addons/base/models/ir_ui_view.py", line 2044, in _render_template
    return self.env['ir.qweb']._render(template, values)
  File "/home/odoo/src/odoo/17.0/odoo/tools/profiler.py", line 292, in _tracked_method_render
    return method_render(self, template, values, **options)
  File "/home/odoo/src/odoo/17.0/odoo/addons/base/models/ir_qweb.py", line 593, in _render
    result = ''.join(rendering)
  File "", line 39, in template_840
  File "", line 28, in template_840_content
  File "", line 1716, in template_842
odoo.addons.base.models.ir_qweb.QWebException: Error while render the template
ValueError: Không thể định vị phần tử '' trong chế độ xem mẹ
Template: website.layout
Path: /t/html/body/div[2]/header/t/t[1]/div/div[2]/t
Node: 

/