Thai streaming platforms use geo-restrictions to prevent anybody outside of Thailand from watching their content. They do this to comply with the licensing agreement they have entered into with the content producers and copyright holders of shows they broadcast.
To achieve this, streaming platforms track the IP addresses of everybody who accesses their website. If the IP address is outside of Thailand, they serve the user with an error message that explains they cannot stream the content abroad.
Although these automated systems automatically block users from accessing content abroad, it is easy to regain access to those services with a VPN. Thus, you can actually lift the ban simply by connecting to a Thai server to change your IP address to a Thai one.