I had similar issues. It was related to the KCP/UDP packets and my ISP was either throttling me back or disabling it during certain hours. It would work if I used a hotspot, as the above user mentioned. I then tried a free VPN and that also worked for me since now my ISP had no idea what I was doing. In the end, I used the VPN only for the hours when I couldn't connect and then switched ISP's. I don't need the VPN with the new ISP, and can connect any time of the day now.