Samsung Galaxy S3 keeps losing network connection and need to restart phone to reconnect I've had my S3 for around 6 months and never had a problem. But in the last couple of days it seems to be randomly losing connection to network (T-Mobile): I have to restart my phone to reconnect. Sometimes this only lasts a few minutes before dropping out again.

Anybody else had this problem? I have no idea whats causing it. I have changed nothing on the phone, and the area I am in has good coverage.

I dont get any error msg and all seems fine -- until I try to use it to access Internet; then it tells me "no internet connection" and the internet data signal disappears. If I try to text the text just fails to send, and I cannot receive or make any calls. People who ring say it goes straight to the mailbox.
your sim card needs to be cleaned, also your sim card reader should be cleaned/serviced. Your connection to phone is not completely ok just because of either your sim card is too old and have been used a lot of times in different phones, thus it needs to replaced in this case. if not, then try solution number 1.