CS5 - Liquify - OK button

[vev]

Hi guys, I am little bit new with photoshop and I would really appreciatte if you help me.
I was working with the Liquify tool and when I press OK button to apply changes, the Liquify window disappears but no changes are applied to the picture. So the picture looks like before.

Can you help me please, what is the problem?

Thank you so much in advance.

[Remote-Medic]

Are you working on the correct layer?

[vev]

Are you working on the correct layer?

I am not sure, how can I check that, please?

[vev]

I checked that and I work on copy layer..after i press OK, suddenly appears window "returning liquify result" and nothing happen..

[IamSam]

Hi vev,

In the Liquify filter, make sure you don't have the "Show Backdrop" checked.

[vev]

Hi vev,

In the Liquify filter, make sure you don't have the "Show Backdrop" checked.

Hi

thank you for you answer!

I checked that, and I don't have the Show Backdrop checked.
Please, don't you know what else can be a problem?