Fatal error when user access their full profile when logged in.

When a user logs in to Easy Social and navigates to their Profile page they get the following error message appear

Fatal error: Allowed memory size of 67108864 bytes exhausted (tried to allocate 367111 bytes) in /home/jasoncwells/public_html/plugins/system/sef/sef.php on line 127

If they navigate to other pages eg Activity Log, Achievements, points, etc. from the user drop down they have no issues.

What is causing this.

Thanks