Second and Third level submenu

Hi,
thank you for the great work!

I have one question to ask you.

I have created a menu structure which is something like that:

• Home
• Menu Item 1

• Sub Menu Item 1

• Sub-Sub Menu Item 1
• Sub-Sub Menu Item 2
• Sub-Sub Menu Item 3

• Sub Menu Item 2

• Sub-Sub Menu Item 1
• Sub-Sub Menu Item 2

• Sub Menu Item 3

• Sub-Sub Menu Item 1
• Sub-Sub Menu Item 2

• Menu Item 2
• Menu Item 3

….

The problem is that when I click on “Menu Item 1” I can see the :
Sub Menu Item 1
Sub Menu Item 2
Sub Menu Item 3

And when I click on the “Sub Menu Item 1” to see the second level submenu items the dropdown menu is just closing instead of showing the sub menu.

What might be causing this? Maybe the theme doesn’t support second level submenu? If so how can I enable this?
Thank you in advance!