OK... so you have "Fiber optics" internet.

not entirely.


from the trunk to the switching station, yes.
from the station to your local "neighborhood" switch... most likely.
from that switch to your house, not likely. Probably twisted Pairs, Depending on the age of your home, probably not so good twisted pairs.

seriously, call your provider, get a line test.
Once it fails get a tech out to fix it.

If you have a huge problem with them, Threaten to get Satellite Internet!

Not so good for real time applications, great for general cache-tolerant usage.