The modem was malfunction again

After the upload of the Korea photos on Thursday, April, 10 (~ 2 hours time), I could not accessed the internet again. I-cable scheduled to check it on Friday night, 18:30 - 22:30. On Friday ~21:45, I-cable staff told me that It might be caused by the outdoor services, therefore the service man was no-show. She said " If I cannot access the internet later, She will arrange the service again.".
Since I had to attend a course whole day long on Saturday,April 11. I could not access the internet.When I asked my wife to check the modem led status at ~18:00 Saturday, It was still abnormal, therefore I reported to I-cable and she arranged the service on coming Monday.
On Saturday night, ~22:00, I switched on the moden again. The leds told me that it was normal.
I do not know when It will be breakdown again.