Run.py - OSError: [WinError 10013]

(mflix_venv) C:…\M220P\mflix-python>python run.py
Traceback (most recent call last):
File “run.py”, line 16, in
app.run()
File “C:…\M220P\mflix-python\mflix_venv\lib\site-packages\flask\app.py”, line 841, in run
run_simple(host, port, self, **options)
File “C:…\M220P\mflix-python\mflix_venv\lib\site-packages\werkzeug\serving.py”, line 795, in run_simple
s.bind(get_sockaddr(hostname, port, address_family))
OSError: [WinError 10013] The attempt of access to a socket is made the method forbidden by access rights

OS: Windows10

This error disappears when the app.port is changed ( default port 5000)

app.run(port=5555)