I had the same issue, it started a few weeks ago, when they appeared to do some maintenance or that was the word from the call centre (081180) I went into the 8ta shop to ask them when this error on contract users will be fixed, they were sort of unaware of the problem people were having, and advised to call 081183 instead, the first time I called i got no answer the second time a technical person answered and assisted me. It seems the *ta software that is on the wireless device sometimes fckes out and then your connection does not work. He got me to create a new connection through Windows and now it works perfectly. Go to Control panel, Network and Internet - Network and sharing centre - then click on Set up new connection or network, I used the Dial up one, Just enter the number *99# Rename the connection to your preference, and click connect. it will connect and maybe disconnect, click on add the connection anyway. Then go back to your adapter settings and the new connection will be there, Double click it and click to connect. You will have internet. launch the 8ta software after the connection and it will show your connection like normal.
That worked for me and it is always on, remember to change the idle time settings if you want to keep the connection always on.