It happened last weekend when I was there in Tripoli(Janzour) and faced similar issue for 2 days, the signal strenght was full bars but no internet. I was told it's to do with Wimax low quality antennas in Janzour which from the heavy rain fall have gone down.
It happened to me the other day and I found out I needed to put 40LD, for the month, on it because it had past the year mark on the initial purchase. I think I have to do this every month or figure out how to pay for the year in advance.
The only option is to re-charge by internet cards. You can buy cards worth LD 480 and load them all at once which will give you the balance for the whole year.
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