If you are experiencing the error "invalid response code 403" it is likely your ISP is blocking our service and you will require to use a VPN to watch our service, one known ISP that causes this issue is AT&T/Vodafone.
If you're already using VPN, then it means there's some issue with their networking, causing this issue (mainly CG-NAT usage).
VPN provider ExpressVPN started using this method, causing our service not to work with their VPN.
a. Try switching few times location, to different countries.
b. If you switched through several locations but still getting that error, then please use different VPN provider.