Jquery ui -dialog box automatically close after first ajax call.

Jquery ui -dialog box automatically close after first ajax call.

I have jquery ui dialog box.
I want to do some ajax operation while dialog is open.
I am using response of first ajax in to second ajax call.
while I am doing this my dialog box is closed after first ajax responses successfully.
so I want to open dialog until I complete both ajax successfully.
Please help with this..

Thanks,