Access to Database deny by OS

[MITELMX]

Hi all,
I am running a budget application on my Citrix farm, but when i try to access i got the next error message:

DB-022
Access to Database MASTERDB denied by Operating System
Analisys Server Error 6009. Too many invalid logins'

The weird is that i got this message at the first time to access not many as the message send.

And then i need to close and open again the application.

Do you have any idea?

Please advice.

Thanks