Where can I claim my online credits?

I am not exactly sure what you mean but I will still try to help.

Are you talking about the "Pending Credits" at that it shows when you place in an event? If so than you have to wait for the event to finish (the timer in the top left corner) and the credits get placed into your bank when you exit to the globe/rxplore/main screen.

You will see notifications pop up that show you how much you made and in what events, this is because you can get knocked out of position by some one else placing and not place in the event. Hope this helps, if not give more info please.

Also note that you need the online pass included with the game to collect credits earned from Global Events.