Roku does not provide support for the TVs, as they are not the manufacturer. They only provide the operating system. I've seen that error message posted here before, but I can't recall what the issue might have been.
If your WiFi password has special characters, (such as !, $, & or similar) that might be the problem. Roku devices will only connect if the password is just letters (upper and/or lower case is fine) and numbers.
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