Hi there,
After checking on your site, it will always follow this menu
http://take.ms/9rHg8. I have created a new menu that is member menu as you can see here
http://take.ms/frxi8 as your "memberships" menu got issues where it cannot be saved anymore and need to be changed currently.
I am afraid to do any changes in it as it might be not behave correctly now. I have made new menu and it should be accessed using this link
https://les-ethipreneurs.com/index.php/member/invoice/confirm/8O56WJCMAUGY
You can configure them accordingly. *change member menu accordingly.
Please give it a try and see how it goes.