SSAS live connection problem

Hello guys,

I have a probleme when trying to connect to my SSAS server in live connection mode :

More details : 

I have a SSAS server which is on another domain than my PBI desktop so I use a runas file to lunch power bi with my credentials (domain\user name and password). Then I try to connect to the SSAS server with a live connection but I have the following error : We could not connect to the Analysis Services server because the connection timed out or the server name is incorrect

I don't understand why because when I try to connect to the SSAS server with the import mode I connect successfully but it doesn't work with the live connection.

I wanted to try on Excel with a runas file, it didn't work at the begining but then I added the port number to the SSAS server and it did work, I could connect to the SSAS server in Excel.

I tried this tip on power bi by adding the port number but the error is still the same.

I am confused, I really don't know what is the problem with the live connection to my SSAS server.

Any idea please on how to solve this issue, it is urgent.

Thank you