A update of this situation.
I managed to enter my router sittings and changed the leased time to 7 days.
I also had a talk with my provider over the phone, and they said that they will shift my routersittings into another channel, so I don't have to bother getting this problem once again. Though I have my doubts about it, because right after the router got restarted from their system, it took 10 min before the router was up for the new configs (channel), then I noticed my pc kept on giving me DNS not working problem again.
I can see we have done pretty much everything to solve this problem, and I kinda got to that point where I do think about that new netcard right now.