Alert Inbox message ..Two languages .. Messages not diplayed ..

Hello all

Can someone can tell me how do I have to maintain my logon category alert in order to display the message in my RWB alert.

In my RWB, alert language appear in spanish language and sometimes no.

I have my category alert logon in english and when the rwb appear in english I can see all my alert messages in the rwb . When the rwb alert inbox appears in spanish messages are not displayed ...

What´s the problem ? How do I have to configure RWB ? Do I have to change something in my browser settings ?

Thanks 4 help