Not able make a thread stiicky

Can anyone advise me why can't i make a thread sticky in my forum?

I can't do selection at all.

Thank you Sanket,

Over at the option column.

Where there a box where you can select/tick is missing. 

I can't select or tick.

Can you post a screenshot of what you see.

Hi Sanket,

I'm not sure why but it ok for now.

The box are back and i'm able to select/tick

Thank you very much