Group By Pandas Datframe and Get Counts

Question

I have a simple question but somehow I am not getting the results.

My data looks like:

Pagename UserId
A           X
B           X
C           Y
A           X

My question is this:

I want my data as:

UserId  PageName Count
 X         A      2
 X         B      1
 Y         C      1

I know how to get this in SQL, but how to do it in Pandas?

I keep getting the error: ValueError: No axis named user_Id for object type <class 'pandas.core.frame.DataFrame'>

for df.groupby('name', 'user_Id').size().reset_index(name='Count')

and data

                                     name                 timestamp
user_Id
buD00         Clicked Back to List Button  2018-05-20T11:00:00.035Z
cWH00    Clicked Create New Ticket Button  2018-05-20T11:00:00.051Z
huB00     Clicked Ticket Reference Number  2018-05-20T11:00:00.067Z
hOH00     Clicked Ticket Reference Number  2018-05-20T11:00:00.067Z