Unable to install app in Responsys

Hi expers,

We have created app in AMS and the publication status is developement.

After whitelist to our Responsys instance accout, we can start to install app:

But it takes long time to install the app to Responsys instance:

Then finally, we got 504 gateway time out as my screenshot:

Have you got the same error before? And how do you resolve it?

P/S: My network connectio is really good and no firewall there.

Thank for your help.

Cuong Tran