HTTP 403 'Rate Limit Exceeded' ERROR in Google Blogger v3 API

I have a python script which uses Google Blogger API with oauth 2.0. Now the problem is that there is a function blogger.posts.insert. It is returning an error "HTTP 403 'Rate Limited Exceeded'".

Can anybody tell me how to fix this? I also tried to do the same in python and the error is still there..

Note: blogger.posts.update function works perfectly!

credentials = storage.get()
http = httplib2.Http()
http = credentials.authorize(http)
service = build('blogger', 'v3', http=http)
TheBlogID = 'somethingHERE'
print "fetching posts, please wait!"

posts = service.posts()
thisposties = posts.list(blogId=TheBlogID).execute()

posts.insert(blogId=TheBlogID, # THIS IS THE PROBLEM
   body=body, 
   isDraft=False, fetchImages=False, fetchBody=True).execute()

EDIT: Also I must tell you that just a few minutes ago I created credentials by selectingWeb Application here : https://console.developers.google.com/apis/credentials? but it stopped working after adding 50 posts and so I switched to other. Also I tried to create a new credential with Web Application but the redirect URL for urn:ietf:wg:oauth:2.0:oob is denying so currently I am using other as credential for oauth 2.0 and getting this error when trying to insert ...

I also tried from here: https://developers.google.com/apis-explorer/#p/blogger/v3/ Same ERROR... I'm assuming this is some bug with google API...