Why does it sometimes not return a token when requested?

Question

API

I use the following request (getting a token by login and password):

url = 'http://oauth.vk.com/token'
scope = 'notify,photos,friends,audio,video,notes,pages,docs,status,questions,offers,wall,groups,messages, ' \
             'notifications,stats,ads,offline,stories,email,market'
params = dict(v=5.124, client_id=app_id, scope=scope, client_secret=app_secret,
                      grant_type='password', username=login, password=password)
res = requests.get(url, params=params, headers=headers, proxies=proxies, timeout=timeout)

But sometimes a response like this is returned:

{'extend_fields': ['birthday', 'avatar'], 'sid': 'c56defa93sdgf4ghd0c9cccbc', 'extend_fields_values': {'birthday': {'day': 21, 'year': 1977}}}

Although it should return access_token and other parameters

So, why does it not return and what needs to be done to get a token in this case?

Answer 1

If you do not specify the API version in the request, then everything is returned normally ...
if anyone knows why, it would be interesting to read