[BC] Surf Internet: blocking external access

I'm the customer of "Surf Intenet" in BC, which is a reseller of Shaw. And for a few days, my external access seems to be blocked. I have few websites on ports 80 & 443 (NextCloud) and StorJ which generates about 1TB monthly traffic. And now all connections from outside are timed out: curl: (28) Failed to connect to ****: Connection timed out Even ICMP pings are not coming back. I called "Surf Internet". They said: we are not blocking anything. I can't call the Shaw, because I'm not their customer. I tried a new router. Nothing changed. Any idea, what's the issue might be? What else I can try? I can only think of switching to the new provider...