Welcome to the AndroidForums, walangmaisipeh.
I see from the title of your thread and from a quick use of Google Translate, that you're having trouble sending and receiving text messages.
Unfortunately, Google Translate doesn't give all of the nuances of your particular issues, so its going to be difficult for our members to try to help since this is English language site.
Please let us know if there are other details that might help the good folks here in the Galaxy Y forum to try to help.
Cheers, and again, welcome to the AndroidForums!