Using a different DNS server not provided by the ISP would most likely solve the problem. You can do so in either the router or your computer/phone. Two well k

Using a different DNS server not provided by the ISP would most likely solve the problem. You can do so in either the router or your computer/phone. Two well known and performant public DNS servers are found at 1.1.1.1 (CloudFlare) and 8.8.8.8 (Google).