TortoiseGit keeps asking my Username and email, but I have already set it.
I also already tried setting it but when I click ok it just redirect me back at the same window.
Git needs your user information for committing, including user name and user email. So, you have to config them first before commit.
Form the figure you provided, you might lack the user name.
BTW, most people usually config them at Global level, the steps:
[NOTE]
TortoiseGit will show you the following message box when you go Git page first time:
Git uses the concept of a hierarchical configuration. I.e. there are multiple levels; settings in higher levels override values in lower levels.
The Effective tab shows you the effective values for the current scope (read-only).
Select any level to see the values stored there. In order to change settings select a level, enter the values and select where to store to.